You are a sanity saver! I got my '04 Aztek last August as a gift & since February I've had a plethora of issues that I've had to fix. Mostly normal, high-mileage, old-car issues except for the few remaining weird, pull-your-hair-out issues that have had me quite batty. Thanx to this video, as well as comments and replies, I now know what to do. And for the first time in awhile, I am eager and ecstatic to be spending the next couple days in the garage. Thank you so very much for sharing!
Thank you for taking the time to make this video, by 2003 aztek overheated and left me stranded, Now that I have it back in my garage and after watching your video I am confident its the head gasket. I will be watching your other videos and tackling it myself, Thank you again for being the type of person who helps put knowledge like this out there for people like me.
5.17.14. The Dexcool coolant will degrade the L.I.M. Gaskets, along with the head gaskets if the coolant is not completely drained from the system. The engine block has drain plugs for both cylinder banks. The back bank drain plug is located between cylinders 3 & 5, & is difficult to access. People go way too long on the coolant service of the system. 2yr/30k miles is what I go. Also the EGR passage port in the upper intake manifold clogs up with carbon, causing a poor or stalling idle. I pulled my engines L.I.M. Off at 82k miles and the L.I.M. Gaskets were just showing slight signs of degrading, not leaking yet. I decided to pull the heads off to inspect the head gaskets. I found that the Dexcool was degrading the head gasket where the opening for the coolant in the block met the opening in the head! It was not leaking yet, but would have in time! I use Fel-Pro metal framed L.I.M. Gaskets & SD head gaskets. Another source of oil leaking is the oil pump drive O-ring located near the flywheel end of the block.
Yep you hit it right on the head! The previous owner of my 04 grand am 3.4 had changed over from the orange dexcool to the green and saved all the gaskets that way! I got lucky, unfortunately the transmission has issues after it warms up from freeway speeds. When i come to a stop it shifts hard into the next gear all the way to fourth, so i feather it as well as power shift to shift it sooner so it lands a softer shift.
@@johnanderson5500 if you can, hook up a scantool and monior data, see if the mass air readings and everything is correct. Shift strategy ,etc use a lot of Inputs
the 3.1l didn't so much have head gasket issues but it dose have intake gasket issues. I hade to replace the lower intake gasket on my 91 Pontiac 6000. he'll of a motor though. ran the shit out if it everyday and when I traded it in it had 315,000 miles on it and it still ran like a top
I have a 1999 Silhouette with 300,000 on the vehicle, replaced trans and engine around 150,000. I intend to drive it until I replace it with a flying saucer :) . I made a modification to the coils and wiring to make it easier to access. I straightened the L-shaped aluminum mount upon which the coils and ignition module rest, then mounted them on top of the intake manifold. It still clears the hood, but makes it much easier to get all those parts in case the coils or module fail. I came about this because a had a no start, that seemed as if it was an ignition module, but turned out it was a broken wire from the crankshaft position sensor. I am prepared to fix this on the roadside, so I try to keep spares with me for things that often break.
you are also knowledgable on these engines. i did my head gasket job back in 2010 70k and an in car partial rebuild of my 160k trans. (clutch pack, sun gear, 4th gear, chain, bands) needed for a failed sun gear and work clutch packs) when i used to put my car in gear, there would be a slap - turns out there also was no hardened chain in the trans, and it stretched, and caused that annoying slap. anywho, something worth mentioning is that GM recommends to keep the surge tanks filled up to full hot when the car is cold. this is extra insurance against the surge hose sucking in air on a slow coolant leak and causing hot spots that can damage the head gaskets. i had my 3400 in my Chevy Venture van since new in 2002 and only have ~185,000 as of May 29, 2020
i have the 3400 when its idleing in drive it gets hot and than goes back to the cold side but it dont over heat it actually runs goood and another thing the code p0401 keeps poping up i changed the egr valve and it stilll pops up thanks alot besafe always have a great beautyful day
Do a coolant system pressure test to check for any leaks in the system. Could just need the air bled out and coolant topped off. The EGR 0401 code is likely carbon build up in the passages. Take off the throttle body and EGR. Run a hard wire down the port and clean it up, suck out the carbon that comes down through the intake. VT247
I ran a direct wire and removed my thermostat put some blue devil and it's been running good for 2 years with no engine problems 2000 chevy malibu Ls 3100v6
@@Shellie-5 was your temp gauge reading normally before replacing the sensor? Or was it always reading all the way cold or hot? Jw, I think I'm having the same issue with my van...
Here's one for you: 2000 Silhouette 3.4 was overheating. Replaced t-stat because it was sticking. Purged air using a hose tee on the heater hoses and raising it above the rest of the system. Purge, fill, repeat until there was no air left to purge. Both fans operating. No white or otherwise unusual exhaust smoke. Engine ran great, heater was hot, temp gauge fluctuated but stayed generally in the middle. Took it on the highway for about 5 miles at 50-55 mph and began to hit the red zone. Tried using 3rd gear to accelerate coolant flow but that didn't seem to have an effect. Engine started to lose power as I pulled off highway. Slowly opened hose tee to see if there was air in there again, and there was a lot. Released steam slowly for about 5 minutes, then started it back up and drove it home. Had to release steam two more times to make it home. Possible diagnoses: 1.) Head gasket dumping exhaust into the coolant and pressurizing it, but if that were true wouldn't there be white exhaust smoke? 2.) Water pump not moving coolant fast enough and it's boiling. 3.) Radiator plugged with rust and Dex-Kill goo. 4.) I didn't really get all the air out.
Pretty sure it's a blown head gasket. These engines are known for gasket failures. Might try a coolant system pressure test and see if it holds pressure. Could try a chemical test and check for exhaust gases in the coolant. It's a blue dye that changes color in the presence of exhaust gases. If you do have to fix the head gaskets, do the entire engine, timing cover, head and intake. They all go out eventually on these motors. VT247
@@Vacationtime247 Forgot to say I did go to AutoZone and rent a pressure test kit. It held 16 psi as long as I could hold on the GM cap that didn't fit perfectly. A full 60 seconds maybe; didn't get a chance to fix the cap issue. I was also thinking of the chemical test. If it's a head gasket, I don't have the time or space, and we'll just hock the van on craigslist and try and get $400 for it.
I'm the kind of guy who buys cars before I go to RUclips to find out that there're entire videos dedicated to the stupid problems that these engines have.
Rodrigo Batista dang, that is really low miles for it to overheat. i'm sorry about that, i'm sure you were upset. and i know i've heard and read a lot about these cars overheating, electrical issues, and rear end noise. luckily i have none of those besides the rear end noise (going over bumps) other than that it seems to ride nice. guess it's the chance you're taking whenever you buy a car whether it's new or used
Wow I have been messing with my 97 Venture on and off forever! When it runs...IT RUNS!....I learned SO much from this one video about my Mertha...Do you recommend any sources that are HARD CORE Venture specific? New tuck is toooo expensive right now!
02 Venture van 3.4 temp gauge straight up 12:00 should be about 212 deg F. T stat is set for 195 full open . Each increment is about 7 deg first mark is 156 f. Low speed fans on at 220 f to 230 both fans on at AC on or above 230. Red line starts at 254 f Top red line is 268. always use factory OEM T Stat. Wide swings are normal but listen for fans and when ideling on hot days it may go to 3to 4 hash marks past 12 oclock .. I use Prestone , dont mix with Dexcool . Purge the dexcool completely and replace , change about 2 yrs Good luck
Mine tends to take forever before the needle moves into the normal range. Then if I am stuck in traffic on a hot day, the needle moves up quickly to near the red. I suspect a partially stuck thermostat in the open position, but I stripped the bolt so I will not be replacing it. Or it could be just bad design. Since I got this van as a gift, I don't know what it was like when it was new. Every car I have ever driven, the needle of the temp gauge is rock steady once the engine is warm. This one seems to fluctuate wildly.
@@lwh7301 Mine fluctuates quite a bit as well . Take note of my previous post as to temp increments . the fans should come on as I said . Near the RED ouch it can get close but should shut down to 212 straight up once the 2fans cick on . You must find a way to change to an OEM t Stat they are more expensive but if you dont want intake leaks or Headgasket repair you need to address it unless you drive it into the ground . the cooling systems on these vehicles are problematic if you dont keep and eye on them .
@@oldtimedrumcorps The fans do come on, but seeing the needle go up causes anxiety when I am stuck in traffic. Once the van starts moving, the needle drops back down. I doubt the thermostat was ever changed. As you know, it's not the easiest thing to do. I got a Stant thermostat 3 years ago, but stripped the bolt, so I never was able to replace it. The van has over 200K miles, and drives great. I use it only when I need to haul big items. So I may just leave it the way it is, and the van never over-heated, just gave me a scare since I have never seen temp gauges move like that. And if it blows a gasket in the future, then I will surrender it to California for $1500.
@@lwh7301 is the coolant green or brown Try to not mix . dexcool is brown ish leave it and only top with dex cool. Still Dexcool is a problem if air is introduced in the coolant . I would put in a new temp sensor they are not expensive . Sounds like rather than getting too involved you might just run it as long as it hasnt given up the ghost Mine will run up high I put it in park if i sit for a long time . It wll drop about 30deg when if both fans kick on . Hers some fun facts . the first has mark at cool is 153then each is 7deg more at top dead its approx 212 degf in the summer it will be around 212 and move up to as much as 235 before both fans come on it then drops quickly or if i resume driving . BTW I get antsy when it gets up there so i dont like to sit forever at the star bucks window . Good luck
Thanks for the great video.. at 2:05, when you're pointing out the intake temperature air sensor, there is a small 90 degree hose that also goes into the intake and is followed into a hole in the engine around back. it's fairly short, about 12 - 14 inches. Do you know what it's called and what it's for? I broke mine while removing the intake in the middle of winter and it was fairly brittle. I spliced it back together with a flexible clear braided PVC hose until I can find a part number. I'm hoping it's not damaging because it's also PVC. but I'm not driving the vehicle at the moment until I'm sure. Thanks for your help.
+Rahim D. That tube is for crankcase fumes to be recirculated back through the engine. Not sure if it's got an exact name. PCV crossover tube. As long as it has a good seal and doesn't have any vacuum leaks it's good. Might have to get a replacement from a junkyard. VT247
Seeing that it has an iron block(if I'm not mistaken).. As long as you change fluids religiously and take good care of the top portion of the engine(all aluminum) it has the capacity to go 300,000 miles or more..
Thank you so much i have an 2003 alero & im dealing with this same problem again it ran hot but instead of getting a regular 3400 motor head i got an super charge. & it started over heating & misfiring so when i pour water into it its comes out the motor head.
Wonder if one or more of the head bolts got stripped out. But the head has to mate with the block right or else it will certainly spew water all over. The GM 3400's had problem with their gaskets. Best to rebuild the entire thing with new gaskets if your doing one. Because eventually, the head, timing cover and intake gasket will all eventually leak. VT247
Take it for what it's worth: I got my 04 Venture with almost 50k miles on it. Now it's at 190k and the only non-routine things I've ever had to fix were fuel pump @140k and water pump @ 175k. This is the best car I've ever had. I also have an Aztek currently with 140k on it. In 60k miles I've changed water pump and nothing else.
Bought a Impala new in 2000. Highly maintained it. 130,000. Both heads cracked. New loaded GM heads were a good deal. Lucky the colant leaked into the combustion chamber.no Water in the oil. Took me 3 days to install both heads. Getting slower at 58 years old.
No kidding. Not getting any younger myself. Used to be able to work all night on a car then wake up and do it all over again. Now, the ol' back makes me pay for any work done the day before. lol VT247
58 is getting old! 🤔🙄🤭 I turned 80 last week. I bought an 06 Buick Terraza with 3.5 cheap because it started to overheat. I tried everything short of gaskets. Nothing worked. No cream on rad cap or dipstick, or oil on surface of coolant. There's combustion gas in cooling system, so I am now half way to complete. Got FelPro gasket set. In Missouri it's a bit warm to work on cars outside. My heads are not cracked or warped, so almost ready to put everything back together. I don't think I'll be able to do this many more years. Most of 3 days so far. Hope to drive it within a week.
I push coolant into the radiator with the coolant exchanger (under light pressure) till coolant comes out of both bleeders. Found it the fastest way to get air out. I am at the point I have to do the gaskets though
Yep. Me too. To hell with Chevy Venture and the 3400 v6 engine. Everything said here was spot on. Be prepared for over heat problems and head gasket jobs. Iam junking mine. Just blew gaskets for the 2nd time in 2 years. Stalled on me about 5o ft from my house at a busy intersection. Had hazards on. Still got side swiped. Tore the whole passenger side to hell.
I have an 03 silhouette. Last year i did a head gasket replacment due to engine over heating. Our one means of transportation. Ran top notch till it all of a sudden threw a po303 code. Cylinder three multiple Misfire. Spark pkug and wires and coils all check out ok. Issue is when you try to accelerate it tries to bog down. Check engine light startd to flash. Once gas pedal is released engine light eventually goes back to solid on. Checked ohm reading on the fuel injectors and got 11.6 on #3 and #1. Still main mode if transportation so any and all feedback is welcome. Thanks
Here's what I'd check if it were mine. Getting to the injectors can be difficult. Check each injector with a noid light, make sure it's getting power. While it's dark outside, mist water around all the area's of the #3 cylinder and make double sure it's not the spark system. Had coils that look good but are cracked and will throw blue sparks if there is a mist of water around it, causing it to misfire. Might swap the coil pack and wire to another cylinder and see if the misfire moves. Could try tapping on the #3 injector to see if the idle changes. Just a few suggestions. VT247
Vacationtime247 thanks. I tried swapping coils and it still had same code. Its hard to grt to the injectors like you said so how would you suggest reaching them with plenum on?
at idle there really is not much of a mis that is noticeable. But I will try the water trick to see if spark is jumping out of #3 coil area. Stay tuned...
Very informative, thank you for taking the time to make this video. I have a question about my 2000 3.4l Impala. I'm having a problem with the bank 1 sensor 1 o2 sensor. The scan tool I'm using shows a negative reading during live data. I have another Impala (2003) 3.8l and it says the same thing on sensor 1 bank 1. I was just wondering if it's a common issue or if I'm doing something wrong. I've replaced the sensors, I've used cheap o2 sensors and I've used expensive ones but it still doesn't help.
Thank you for all the info. I have a 2003 olds alero with the 3400 and it has been overheating but it also has been throttleing on it own. I will be going 45 let off the gas and it stays at 45. So my wonderful mechanic first had me buy a water pump then the temp sensor and he was sending me to get a thermostat when i noticed that neither of tye fans where running and it was well above temp at this point. So i check fuses and cleaned relays but fans still dont work. What do u think. And i checked the oil cap and dip stick and do not see any white residue nor can i spot a leak when u showed to look. I truly appreciate your help.
Bleed the system of air. If it runs fine for a while then overheats along with again having air in the system, it's probably a bad head gasket. Might try a system pressure test to confirm. As far as the staying at the same speed, check for vacuum leaks and if the throttle body is closing all the way. To test if the fans work, unplug the temp sensor and they should come on, but this will trigger a code. Yet, it's a quick easy way to tell if the fans are working. VT247
Vacationtime247 WOW man I didnt really think you would respond. I wasnt sure like how old your stuff was. I really appreciate it. I think my biggest problem in the situation was the guy who I thought was a mechanic but it turns out he is good and putting on new parts which if i had a garage full of tools and RUclips i could probably do. So today an old newer friend of mine called me and i totally forgot he us a certified mechanic and works at a shop. So he looked it over today and tomorrow he is going to take it and fix all this crap. I will pass on your info. He did say that i definitely have to buy a tensioner pulley because he could actually see it moving around and its possible that was causeing the throttle issue. And once again I really appreciate it it's good to know that I can reach out to someone if i have anymore issues.
I've got a heap of a 1997 oldsmobile HELL-OH-ET with the 3400 engine and it is leaking coolant from the passenger side of the engine . I think it is coming out somewhere by the water pump or tensioner pulley assembly but i can't see for sure . I do know it's not coming from the radiator or the hoses. It's almost seeming to be accumulating on the face of the water pump pulley and getting spattered on to the radiator and the control arm etc , but it seems like it's barely accumulating when I'm parked and the engine is idling. I believe driving is when it leaks the worst due to there being alot of coolant in the areas i specified when i popped the hood to inspect the sweet coolant smell i smelt when we were driving it home . There is no coolant in the oil and no bubbles in the reservoir and the heater works great , i just replaced the temp. Control sensor and bled the system properly . If you have any suggestions my email is canjojohn02@gmail.com and i would appreciate any suggestions at all . Thank you , sincerely ,Rod
Thank you. This video was very helpful. I'm going to try your method on riding the over heating problem. Hopefully it clears the probpem. Again Thank you
I have a 2000 Impala w/ 3.4 and it seems work as far as morning startup and running the heater, however when you look at the temp gauge it will be 165 or so and only one time I put coolant in was when we found a cut or bad area to the overflow eank at the radiator, we cut off the bad area and replaced no more leak. But yesterday I had to make a road trip of about 60 miles oneway going down know problem 59 outside temp, coming back 72 outside, about 175 on temp gauge and when we got 12 miles from home the message center flashed LOW COOLANT LEVEL, I pulled off the road and checked coolant tank and it was 4 or 5 in down from top, both hoses had pressure and never got to midrange temp untill I got home. I checked levels the next day and everything was fine. Now the Service Engine light in the message center is always on, been reset I dont know how many times, got it on a big computer and the only thing he could find was a BCM maybe bad or what have you, but the system itself is fine. Would the BCM cause something like I mentioned ??? The car sit for 2 years, because the lady bought a new car (traveling nurse) The gas cap doesnt stay tight, the radiator cap (looks) like it could be replaced (but not leaking that I know of) As far as water pump or thermostat I dont have a clue. Im disabled and I needed a car and was given this one, but I cant afford any big repairs. Can you PLEASE HELP ME ??? Thanks
There may be a coolant level sensor on the car, may be faulty. Also try adding fluid all the way up and then bleed the air out of the system when the car is at operating temp. There should be two bleeders. One on top of the water pump, the other on top of the water neck outlet by the thermostat. VT247
On my Venture, the coolant level sensor is on the end of the radiator below the radiator cap. If the coolant level is 4 or 5 inches down, then the coolant level sensor should be signalling low level, which in your case it did. I recommend using a spill-free funnel for bleeding the air out of the cooling system. That's what I use and it works great. You should do a coolant pressure test though to check for leaks. You should also check to make sure the head gasket isn't blown. Use a combustion leak tester to determine if there's exhaust in your cooling system. Also make sure there's no oil mixed with your coolant or coolant mixed with your oil. When you fill up your radiator, also fill up the coolant reservoir to the hot level line. GM recommends filling it to the hot level line while the engine is cold to ensure no air gets drawn into the system.
I have a 2002 Chevrolet impala 3.4L that overheats when going up mountainous roads during summer. Coolant is level, fans work, thermostat works as it should, new coolant pump, and just has coolant system pressure test done but can't figure out the problem. Live in Southwest Virginia
Sounds like you've covered all your bases. When you say it overheats, does it puke out the overflow tank? If not, then it may just be getting hot but not necessarily overheating. Only other suggestion would be to make sure there aren't any blockages in front of the radiator. May try pressure washing to clear the venting fins. VT247
Our mechanic said the aftermarket oem quality water pumps are garbage on these engines. We had the same problem. The intake was leaking and the gaskets were replaced. Then the Gates water pump failed after just one year. The water pump caused overheating again, and it blew a head gasket. The top end was rebuilt, and a GM Goodwrench water pump installed. Since then no problems, and that was five years ago.
Thank you so much, I will do that today. Also I was told to loosen header exhaust bolts that converters was bad for going bad on those, I did check the exhaust and could not hardly feel much exhaust. So I'm guessing I will be trying both today. I will let you know how it turns out, thank you agian car friend.
I've cut out a section just behind the cat converter and then used a hammer and pry bar to bust up the material inside. Then blow it out by starting the car a few times. If after cleaning out the cat, the secondary O2 sensor reads low or wrong voltage, add in a spark plug non fouler to the end of the secondary O2 sensor. Drill out the inside of the non fouler so the O2 sensor screws on inside. Will keep the code from setting. VT247
right on thanks guys! no wonder it wouldn't take more than like a quart of water after it vented at least a gallon into the overflow. it has been sitting since my last post and for the record Vacationtime knows his stuff. Nobody wants to accept that their car has blown a gasket but that ended up being the case with this montana as well. Another one bites the dust! may as well count on any of these v6's to blow at some point and if you get 200kmi+ out of one, consider yourself good a PM tech. anybody interested in picking up this blown out soccer mom/ G ride for a steal of a deal in UT let me know
Mine has had the intake manifold and head gaskets redone. Not smoking and no coolant in oil. Also it's not running hot but I am losing coolant. I can fill up the radiator and start it up and drive it for 15-20 minutes and my low coolant light will come on. I've also changed that sensor as well. Heat works pretty constant. I also have virtually no pressure in the system as I can drive the car like I said and remove radiator cap no problem. Thoughts?
Do a coolant system pressure test. They rent the tool at Autozone. Basically you hook it up and pump up the connector. It applies pressure to the system. Make sure the pressure doesn't drop rapidly. If it does, check for leaks or sounds. VT247
I don't know why I can't see my previous message. Anyway, what is the cable that you touch with your finger for in the min. 5:27? in my 2002 venture the right side cable is loose and I can't see the other part, which has a white plastic part. thanks
Temp is right in the middle. 4t65e seems to desire a few degrees less temp; Ive got mercon atf. ( The normal 2005 atuff) My 4t65e hard shifts (thumps) at temp. So, Q: Any guess? Maybe it is an ATF viscosity at temp? How can I get a few degrees less temp? Maybe some ATF thickener like STP. I am thinking of using 160 stat and hard wiring radiator fan to 100%. Id really like to stop the trans to stop slaming shifts. Kinda think that holding temp at 160 will fix it. I do appreciate your thoughts! Old Timer Richard.
@@Vacationtime247 I suspect I had an air lock in cooling system. The 4t65e needs the correct temp. to function well due to its advancing age. Getting the air out w the bleed screws looks like all it needed. If troubles are marginal, I will add an aft market trans cooler. I do think my valve body needs care due to wear and blow by. Theory is the cooler will keep the viscosity up by preventing excess thinning of atf fluid. Thanks for your knowledge.
I'm working on a friend's '04 Impala that has random overheating issues. There's no bubbles coming out of the radiator when running, so I was hoping it wasn't the head gasket. I replaced a leaking water pump and thermostat and bled out the system; all to no avail. I'm not sure if the leaking caused the overheating or what, but it's beyond obvious that GM didn't put any stock in the engineering or longevity of these engines and the cars they put them into. They earned that bankruptcy in 2009, and it's a tragedy they still have customers after the garbage they sold; but people are idiots and blindly advocate companies that don't give a shit about anything but their bottom line, so go figure... Anywho, I have to commend you on your obvious patience and (maybe) love for these things and defending the 3400. I disagree entirely that they're worth saving because of the inherent flaws and absolute lack of logic in assembly, but you see things differently and that's cool. The Impala I opened with barely has 117k miles on it and is pulling the overheating shit while other systems are failing, so all I want to do is use it as a four-wheeled wrecking ball until it burns (despite how much I hate waste). But you're inspiring me to give it another chance in trying to fix it that will end in my fiery rage :')
Do a coolant system pressure test and see if it holds pressure, autozone does the loan a tool to try it. The GM gaskets that they assembled these engines with were absolute garbage. If it does happen to be the head gasket, check out my video's on how to do a repair / replacement. Currently have 2 of these engines each in '01 Azteks and all the gaskets have been changed in both, intake, head and timing cover. If you do happen to do the head gaskets, it's worth it to go ahead and do the timing cover gasket too. Best of luck. VT247
I sympathize with your frustration. But I would like to respectfully offer an alternative. Spinning a wrench is therapy for me and something I love doing, so I try to just accept the flaws of each engine rather than getting too frustrated at them. There's a lot of satisfaction in getting an older car to run well, and I know it will always cost some money and lots of time to get it there, not to mention a few skinned knuckles and brushing grit out of my hair for a week. Overall, I just find it better to get a list of what usually needs replaced on a certain brand of car or engine and plan on replacing that list systematically. I then reserve my frustration for politics! The satisfying thing is that when I have to do head gaskets, I get to save $1,000 or more by doing myself, and I get 10-20 hours of therapy while I do, and it is me against the world ... I either do a good job and get a good car in the end, or I screw up and have to do something over or junk the car. Fair enough--that is part of the therapy as far as I am concerned. Each engine has its flaws and weaknesses, and it is true for all engines. Even workhorses like Toyotas. My so called "run forever" Corollas leak oil (rear mains at 130,000 and chain tensioners at 100,000), and both needed intake manifold and valve cover gaskets before 100,000 due to hardening of the original neoprene gaskets. My 2003 Corolla ate oil like crazy by 90,000 miles despite having changed the oil religiously and having run only synthetic oil for the life of the car. It still ran well at 170,000 when it slammed into a telephone pole in an ice storm and was totalled, but I had to nurse it along for 80,000 miles of oil level checking. My Subarus have needed timing belts every 100,000, and usually a set of head gaskets as well, and all of my cars have needed struts by 150,000 miles. So with the GM 3400 engine, we know it will need upper and lower intake and head gaskets by 100,000 original miles, period. But then it is good for 100,000 miles more or longer if you use better gaskets. Even the number of things to take off isn't much different from other engines... wiring, fuel rail, etc. And thankfully, you don't mess with the timing like you do with all overhead cam engines...
That's true. Most engines will need fixed at around 100k miles to some degree. The 3400's use a timing chain and no type of fancy overhead valve assembly. That is nice considering they usually last for the life of the engine. Never was a fan of timing belts, like Dodge and other manufacturers use. If it's an interference engine, and most are anymore, when the timing belt breaks, you're getting valves, pistons, possible head or just junk the entire motor. Best motor I've ever had and will still attest to this day was virtually indestructible is the 250 inline 6 put in the 1970 Chevy C10 pickup with the 3 on the tree manual trans. Beat the living crap out of that motor. Hauling loads in the bed that would nearly drag the bumper on the ground was never a problem. Manual door locks, manual trans, manual windows, no factory stereo, manual steering it was so simple nothing ever broke. VT247
Thank you for the information. I have a question on my 2004 impala 3.4 engine. Besides the loss of antifreeze I recently noticed a large loss of oil that I had to add, when this engine previously had no oil usage problems. Can a bad intake gasket cause this? I do suspect a bad head gasket though.
I know this video is years old, but maybe someone can help. 2000 silhouette. The low coolant light goes on and off but there's plenty in the reservoir and radiator. It wants to overheat when idle. No bubbles in the coolant reservoir. No white or milky junk in the oil or the cap. No white exhaust. This lead me to think the gaskets are fine. I'm thinking the thermostat stick closed or coolant temperature gauge might need to be replaced, or maybe there is a clog in the coolant system somewhere? Now I'm wondering if I missed something or there could be a different issue because you state that the thermostat going out isn't all that common. Is there anything else I should be looking for?
I was changing the coolant temperature sensor in my 2001 malibu and the part that it screws into cracked around the sensor was wondering what the part name is it screws into
Whats is the normal operating range on the temperature gauge. I am usually at the 11 oclock and 12 oclock in city driving. But around 1 on highway driving. Thank you for any information
Not sure what the name of it is. There’s a rubber grommet that the vacuum tubing goes into that fastens to the upper intake. Make sure it is fully seated and secure. Might have to remove the metal throttle cable bracket to see or fix though. VT247
I have to say that these engines are bad for the gaskets, but if u replace the gaskets and catch it way before it causes a problem in the lubrication system, these engines can be rather dependable. I have a 2000 monte carlo replaced the gaskets, and its got near 400,000 on it, the transmission went down about 313.000 it's got a little valve tick, but it's not no big deal to me, but these engines are pretty decent if the gasket job is caught in time. Thanks for the video!
I build and mod these engines i have several grand ams i like the car, but i tell every who repairs or is trying to rebuild the 3400 or even the 3100 engine is never go cheap on the gaskets especially the lower intake gaskets i always get the metal gaskets they last forever and also they dont restrict air flow like the plastic gaskets do.
Why does my "97" 3.1 litre chevy run hot? I have changed the relays fan blade, fan motor, flushed the radiator, thermostat and water pump. My car had the head gaskets replaced with alluminum at 134.
RUclips notifications of comments aren't showing up like they used to. If this is still an issue, try a coolant system pressure test to see if it holds pressure. They are known to have bad gaskets such as the timing cover, intake and head gaskets. VT247
I inheirited my mother's 03 rendezvos with the 3400 engine. It's never had anything done to it engine wise, just a ton of front brakes and wheel bearings. When I was bringing it home, the temp gauge flew up to hot and the bell went off and before I could pull over it dropped back down into the normal zone. coolant was low in the radiator about a quart and the overflow was down to where the hose wasn't in the fluid. I don't have any sign of coolant in the oil or any sign that I can find of coolant leak. I've seen a lot of videos on burping the cooling system. I'm hesitant to start tearing it apart without learning more. I also have no heat in the cabin, but tho the engine is at normal operating temp. The blower works on 1,2,4, and 5 and I've seen several people on here saying that heater controls have bad connections resulting in burned off contacts and there is a funny smell, kinda like something is burning. Got any advice for me? Or do you wanna buy a rendezvous cheap? lol
Fill the radiator and reservoir up with fluid with engine cool. Start the motor and bring to operating temp. Turn out the 7mm bolt on top of the coolant neck or on top of the water pump (that black metal pipe). Let the air bleed out and tighten the screw. That should let the heater blow warm air. VT247
I have a 2002 Impala 3.4 and it is overheating... The water pump and hoses have been replaced, and it seems like the radiator is pretty new, as well. After replacing the water pump, and driving it around the block, it was overheating again and hissing to the drivers side of the engine near/in the vicinity of the air filter hose; the end that is connected to the engine, near the thermostat... Help?
Sounds like a blown intake or head gasket. These engines are known to blow the factory gaskets. Best to do both at the same time while it's being worked on. Do a coolant system pressure test to confirm. VT247
Thank you. How much ya think the gaskets and RTV and whatever else is needed would cost? Worse case scenario? I know the labor is gonna be a bitch.... :(
I'm guessing around $150 for the gaskets, RTV and other parts. Labor depends on who and where you have it done. It's not a really hard job to do, just takes a while. VT247
Dude this engine is both one of the most fun I've had with a car when they work good to one of the most mechanically and financially demanding engines I've ever had. My 03 grand am gt jumped time on the first engine and overheated with a new thermostat, and full radiator & new oil. Nearly set the thing on fire with how angry I was.
Best thing to do with these engines is to completely rebuild them with all new gaskets, Head, Intake & timing chain cover. They all eventually fail. Didn't have a coolant pressure system tester until buying one of the vehicles these engines come in. lol VT247
If after running for a while, one radiator hose is very hot and the car overheats but the other hose is cool, the thermostat is probably stuck provided it has sufficient coolant. These engines tend to have issues with the blown gaskets, intake, head and timing cover. A coolant pressure test would be helpful too to find any leaks and see if it holds pressure. VT247
I purchased an 01 Aztek GT in 2002 and really enjoy this vehicle. Over the last twelve years, the intake manifold and head gaskets have been replaced once. I have a problem with the engine temperature gauge showing an increase in coolant temperature when I'm in city driving conditons. At the same time, the automatic transmission starts "hard" shifting. The cooling fans do not run unless the AC is turned "ON". How do I make the cooling fans turn "ON" without running the AC?
The coolant fans will only turn on when the temp gauge gets pretty high unless you turn on the A/C. You could get a tuner program and reprogram it that way, otherwise it is factory set. Mine does the same thing. VT247
Vacationtime247 Hi, Thanks for the video. I have an 03 Malibu with a 3100 engine. It overheats. I unplugged the coolant sensor temperature and the fans come on. The fans don't come on otherwise. What would you look at next if I know that unplugging the sensor turns the fans on high, fans work and fuse it good? I have not tried to bleed the air out of the cooling system yet because the fans don't come on I figure it is electrical. I have seen suggestions of a secondary fan control however I am not sure how they are wired in or if this is the fix needed. Do you have any feedback on this? www.autozone.com/productComparisons/productComparison.jsp?originalUrl=%2Fcooling-heating-and-climate-control%2Felectric-fan-thermostat%2Fchevrolet%2Fmalibu%2F2003%2F6-cylinders-j-3-1l-sfi-ohv%3F Thank you, Matt
Vacationtime247 Situation- 2001 Aztek runs perfect at highway speed, temp gauge reads normal. Then I slow down for city driving and the temp gauge registers a higher temp (needle moves up "1" mark below the overheat range). At the same time, the computer instructs the transmission to raise line pressure and the transmission begins harsh shifting. I parked the Aztek in the driveway with the motor running and opened the hood. The cooling fans were not running. I measured the coolant temp with an infrared scanner and watched as the temp reached 237 F on the scanner. The cooling fans started running on low speed at 237 F and then stopped (10 seconds). I unplugged the temp sensor and both fans ran on high speed. Why does the computer tell the transmission to go into "limp" mode and start harsh shifting? Is there a sensor that is picking up bad information? The vehicle runs great in cooler weather.
+alvinspmn The transmission is trying to save itself from burning up, this is why it goes into 'limp' mode. Do a pressure test of the coolant system and check for leak down. If it does leak down, listen for a hiss or water / coolant coming out. Sorry to say this, but these 3400 engines have a bad reputation for blown head gaskets. VT247
Hey my buddy replaced his thermostat in his overheating 2001 Buick century. Now when he tries to start it up it cranks but won't actually start then possibly a back fire or burp.. what should I look at first to address this? Probably occurred during poor mechanic work
Check your fans. While it's idling in park, turn on your ac and see if your fans kick on. If they don't you have a problem some where. I had that problem which was the ac relay which actually poped and prevented my car from starting because it blew a fuse that shares the pcm with the ac. I own a 2004 Pontiac Grand Am SE1 3.4L but these Pontiacs are almost the same if it has the same engine. Mind you i say "Almost" the same. Anyway what i did was pull out the relay block in the fuse box, and replace the blown fuse i had, then manually hooked both fans up to a switch to the battery. This means i can turns the fans on anytime, but i don't have ac. Hope this helped. By the way if you're ac doesn't work and you don't care you can eliminate the ac radiator in front of your actual radiator for more air flow to keep it cool. Mine was already empty so i cut it off. But if its full your supposed to have it professionally emptied.
thank u for responding so far I've taken it to several shops no one knows so been trying to research why I would have heat, air, holds pressure,no visible leaks, no coolant lost, no milky oil on dip stick did notice little condensation under the oil cap but that's normal right? no unusual colored smoke or consistency coming from tailpipe, fans working no pully loose, belt look fine however at start up does have fume like smell by the way it's a 3.6liter
+drae allen It's possible that the thermostat needs changed out. If it's stuck open it would cause overcooling in most situations. My first guess is that a gasket might be leaking internally because the gaskets on these engines from the factory weren't good. VT247
Dorman heater pipe- would you happen to know what that is? I have a 2000 pontiac grand am gt (black lol) it wouldnt let me leave a pic in the comments but i was wondering if it needed an O ring or somthin cuz i just push it in but it doesnt stay good enough then it starts leaking coolent. It looks like you just push it in but idk if i was missing a ring or somthin cuz it still will start to leak coolent. Very appreciated if you can help
I'm having some serious issues with my girl. SHE'S A 2001PONTIAC GRAND AM SE1 WITH THE 3400 V6 VIN#E SHES got about 167000 miles on her. All the upper intake manifold gaskets and hoses were changed out by the previous owners mechanic as the were leaking about 1 year ago I was driving, pulling into a parking lot. She started sputtering like she was out of gas, (which couldve been possible due to a problem with my fuel gauge stuck on empty no matter the amount of gas in the tank) so luckily gas station was next door. Put 4 gallons of gas in her tank. At times like this as soon as I put gas in her tank she started right back up. Except this time... So far I have released the pressure in the fuel rail, turned key on a couple times. I can hear the fuel pump run. First few times I did this pressure was not there. So I replaced fuel filter. Pressure returned in the fuel rail. I'm not sure what the exact pressure is I have not checked this as of yet. Anyways I know fuel is being delivered to the injectors. Now I have had a plethora of codes comes and go over the last year since I bought her. I'm having an oxygen/emissions code come and go frequently. My ABS /TRAC OFF SERVICE ENGINE LIGHT (located above tachometer)ARE ALWAYS ON TOGETHER. THEy COME ON TOGETHER AND DISAPPEAR TOGETHeR. I've had the right hand side service engine light come and go frequently, more so here lately. After my car would not start up it was throwing a code for TPS and CPS. I replaced the TPS. SHE STILL WONT START. I TOOK ALL SPARK PLUGS OUT INSPECTED FOR BROKEN OR CRACKED, THEN CLEANED THE CONTACTS WITH A PRECISION FILE AND SPACED HER PLUGS TO .060 AS SHE HAD ERRATIC SPACED PLUGS FROM TO .065- .072. THEY PROBABLY NEED REPLACING BUT JUST TRYING TO GET HER STARTED RIGHT NOW. I PULLED OUT THE PLEASE HELP NUMBER 1 PLUG AND CRANKED HER OVER, SHES SHOWING SPARK. I SPRAYED STARTING FLUID IN HER INTAKE MANI. . SHE SPUTTERED A LITTLE NOT MUCH AND SHE DIED QUICKLY... FIRST TIME I DID THAT SHE (BACKFIRED BACK THROUGH THROUGH THE INTAKE MANIFOLD IN CASE THAT WILL HELP ANY. ) SHE NOT SHOWING ANY SIGNS OF LIFE... I NEED MY GIRL BACK.
Sounds like the car has quite a few issues to sort out. So, if it is reading that there is a bad Crankshaft Positioning sensor the spark may be off and not firing correctly. Believe this ties in with the DIS control module. Some TPS units need a multimeter to set correctly as it needs to be bolted in at the correct angle to read right for the computer. The CPS is located by the harmonic balancer and may need cleaned or the wires inspected for shorts or broken wires. An engine needs 3 basic things to run, fuel, spark and compression. Hope this helps. VT247
+frank foster Do a pressure leak down test of the cooling system. Usually this means hooking a pump up pressure cap to the radiator and seeing if the pressure drops. This will also give you an idea where the problem is, coolant will come out and / or make a 'hissing' noise. VT247
My 2002 Oldsmobile Alero has the 3400, My cooling fans do not come on when engine is hot nor when I turn on the A/C. When I unplug the temp sensor the fans with come on immediately and stay on. I still replaced the temp sensor but that did nothing.
How high does the temp get? Mine usually has to be over the 3/4 mark for the temp. My advice would be to hook the car up to a good OBDII scanner and see if you can turn on the fans. Might be that it's not getting a reference signal to turn on the relays that control the fans. VT247
acceleration issues with my 2004 Buick Rendezvous. I replaced the fuel pressure sensor, give it a tuneup, changed fuel filter, cleaned mass air flow sensor, Intake air control Value, and Erg value repaired electrical connectors hub going to fuel pump, checked catalytic converter, checked for vacuum leaks. I press on the gas no power, I go up hill and it loses speed. it builds up speed slow. I will not get on the highway during rush that's a no no. Went to the dealer after no other shop could figure it out. 500 dollars worth of diagnostic testing same problem. I feel like i was ripped off by GM I was told to do this and that same problem. I replaced a fuse it solved a problem, I cleaned the mass air flow sensor, Intake air control Value, and Erg value it solved a problem. I got the same issue but i will pay for anymore diagnostic testing a waste of money. No more check engine lights but same problem. Help Please
Just a few thoughts. Could be the O2 sensor or possibly weak spark (plugs, wires, coil, coil pack module) It needs a lot of spark to jump the large gap of .060 for the spark plugs. VT247
My fans won't come on. Temp gauge works and shows up past center, but fans won't come on. I can remove the top of the relay and push them down and force the fans on high. So motor/fuse/wire is ok. what controls the fans relay? great vid
Does the fan come on when you turn on your A/C? The fans won't come on until the temp gauge is way up. I can let my Aztek (3400 engine) idle for what seems like forever and the fans don't come on. This is because the engine isn't overheating. Does yours overheat with coolant coming out the reservoir? If so, then it may be that the fans aren't operating correctly. Try unplugging the coolant temperature sensor, it can be difficult to reach as it's a tight squeeze. This should turn on the fans as well as it is a default for the computer. But, to answer your question, the coolant temperature sensor reads the temp as being high, sends a signal to the computer (ECM, electronic control module), the ECM sends a reference signal for the relay to activate, the relay then sends the fan 12 volts to run and turn on. Hope this helps. : ) VT247
Right, I used to run the a/c to keep the fans on. The a/c doesn't work now, so the fans won't come on ever now. I bypassed the relay and run a switch to run them manually. Guess I need to see the ecm signal to the relay to prove ecm good. Thanks for responding!
Try unplugging the coolant temperature sensor and turn the car on. If the fans come on, they're working fine. If not, there's a problem. The coolant temp sensor is located by / under where the throttle cable hooks to and by the upper radiator hose. VT247
Ive got the evap issue should i start with the evap solenoid over the gas tank or the part by the throttle body the o2 sensors are reading bad also figured that was because of the evap letting out bad emissions too much unburnt fuel the 3.1 liter 2002 buick century has 85,000 miles on it
Check inside the upper intake where the EGR bolts on. They are prone to carbon up real bad there through the passages. Another evap issue I once had was the check engine light would come on due to a bad FTPS (fuel tank pressure sensor. It's located on top of the tank, but can be reached under the vehicle. VT247
if your watching this, I'm sorry. Stay clear of the gm 3400. prone to intake gasket failure that tends to cause the main bearings to fail. they blow head gaskets easily when they get a little warm. and the cam shaft is known to give out. my Rendezvous has scrapped two of them. my neighbors Century blew up and my brother in-law's Alero has 60k miles and sounds like a sewing machine. look for something with the 3800. much better engine. plus it gets the same gas mileage and makes more power.
Thank you for your videos. They are so helpful! I was wondering if you could identify something for me. I found a small metal tube sticking out of the back of the intake plenum on passenger side. It's right in front of the alternator on my 2002 Venture. It seemed to just have rubber cap over it which had a hole torn in it so I replaced it with another rubber cap. I was wondering if you knew what this tube is and what purpose it serves.
I have a 2000 chevy venture van 3.4L and the idle has been getting steadily rougher for the past couple of months. I changed the sparks recently to fix a separate issue but I still have a dead spot when I first start the engine that lasts only 1 second before the engine kicks in again and idles. Anytime I am idling the engine is running rough and the temperature increases to 1/2 way and up to 3/4 now as well. Temp will decrease at normal speed limits. After watching your video and another one that specifically focused on my make and model, I am leaning towards thinking that this could be either an exhaust vacuum leak, a misfire or an intake manifold gasket issue. What would you recommend I do now? Thanks for your time!
This motor was in an Aztek. But they put the same engine in the Impala for many years. Often GM puts the same motor in several different vehicles. VT247
@@Vacationtime247 Thank you so much for replying. Sorry it has taken me so long to get back to you. The inevitable happened yesterday as a Matter of fact. It was running really hot when I picked my son up from school yesterday.. and didn't make it a quarter mile until it had gotten so hot that it shut down on me as I was driving. Thank goodness I was able to get the car pulled off on the side of the road. I have been so frustrated with it that I haven't even bothered to go back to it and try to see if it will back. I would say I that I probably messed it for good. But again, Thank you so much for ur help.
Hi I have 2003 Chevy venture don’t know what going on but when I drive I have good heat and the temperature normal but when I park or wait for the red light the temperature gate go up hot and no heat. I put new radiator new water pump new cooling sensor new thermostat and still does the same thing I wonder it have to do with the head gasket please let me know thank you
Vacation time, my 3.4 l8tr 2004 grand am overheats but the gauge doesn't reflect that. I believe the gauge works cause it move between 190-215 degrees. But steam is coming out from under my hood sometimes. What do you think?
Get a lot of these type of questions about this engine, so here's where I'd start if it were mine. Do a coolant system pressure test after filling up the overflow with water. Once pressurized, listen and watch for water to come out. Bet that a gasket is blown and it's leaking somewhere. Replaced the head, intake and timing cover gasket on nearly every GM 3400 I've had. VT247
i have a 2005 buick rendezvous 3.4 it seems to over heat after about 30 to 45 min. ive changed the temp. sensor thermostats. an the fans not to sure if my fans kick in properly when i turn ac on they seem to kick in with more speed oil is good no smoke comes out from the exhaust
Ok so I am having trouble finding the bleed plug for coolant on the drivers side. All the videos i have watched show a plug on the passenger and driver side but those werent aleros same engine though. Is there really a second bleed plug on the driver side of the engine ? And just to clarify. The 2 cooling fans , do they both come on at the same time with 2 speeds or no. Because im going out to junk yard to get new fans. My mechanic couod actually feel that the motor wasnt moving right.
Believe my fans are either on or off not variable speeds and come on at the same time together. Could check yours by unplugging the temp sensor. It would set a code off, but would turn the fans on. The code would reset after a few starts. The bleeder screws are pointed out at 2:45 If you're having to continuously bleed air out of the system there's a problem. Doing a coolant system pressure test is a good way to find any leaks. VT247
I just purchased a 02 rendezvous and the only motors that is suppose to come in it is the 3400 but the intake cover says 3100 how can you tell the difference and are they interchangeable with transmission and everything
Hey i have a question about over heating it doesnt over heat completly goes about 3 fourths of the way then goes back down once fans kick on but i believe i have a slow leak where the bleeder is mext to the water pump l.. What type of sealer should i use on that o ring
If you're referring to the metal tube that has the bleeder on, it has an o ring. I took mine off, cleaned it and also added some black silicone around it. Didn't leak anymore after. But, might do a coolant pressure test to find any other leaks and see if it holds pressure after. VT247
Not necessarily. Coolant can also get into the combustion chamber or blow out the side of the engine into the atmosphere. If the engine coolant system isn't under any pressure and circulating correctly, it can and will overheat. VT247
@@Vacationtime247 my 2003 Buick Century is running hot I change the water pump about 6 months ago no leaks I had to change a hose is it good but it just started out the blue overheating and then I tried to bleed the air system and then I did the thermostat so do I have to follow this video
@Vacationtime247 I do not have enough heat, 2000 Montana Van, runs not more than 1/4 on the gauge scale, the heat is not HOT, just luke warm. Thoughts? otherwise it runs good
Fill up the coolant to the appropriate level. Run the vehicle until warmed up. Bleed out the bleeder screws until all the air is gone. If the problem persists, do a coolant leak down test. This will expose any leaks that may or may not be visible. It should hold pressure and not drop quickly. VT247
Have 2003 grand am gt 3.4, started missing, sounded like a knock but was firing it seemed inside intake behind Throttle body. Code is mb ass air flow and #3 misfire. Put on new cool, spark plug, still missing.
Might be a stripped out rocker arm bolt. On some 3400 the threads are not very strong and a small bolt that goes into the aluminum head. Would explain the knock and would also explain the misfire. Take a piece of rubber tubing, put one end where the sound is coming from. The other end to your ear and listen near the valve cover. You can drill and helicoil the stripped out bolt for a fix. Hope this helps. VT247
Ours is overheating after new water pump and radiator, hoses, and it's hissing near the air filter hose; the end connected to the engine, and in the vicinity of the thermostat.... Wondering if and or what hose(s) it could be. 2002 Impala.
good morning Bud. I have an 04 olds silhouette with a 3400 motor and I'm reading 2 codes. 300 & 171 codes. I did an in house oil change and plug/wire change and oil pressure dropped. I have to little flared tip things at opposite corners of the upper intake manifold and they're sulking in air. are these supposed to be capped off or lead into some other intake hose? also, bank 1 code (171) is that an upstream o2 sensor? I changed out the oil pressure sensor already too. my car is riding ROUGH and as soon as I turn on the a/c I lose power. please help.
Sorry for the late response. Been in Alaska working as a mobile mechanic. Back on the Cali coast again. Sounds a lot like a vacuum leak. I shoved a piece of sponge in between the bracket and vacuum tube. There should be no vacuum leaks. A misting spray bottle of water can help find vacuum leaks. Spray and monitor for idle change. VT247
I have a 2003 chevy impala with the 3400. The other day the low oil pressure light kept dinging. Well i ignored it cause it's been doing that since I had the oil changed last month. So as i was driving the car became a little warm, not hot enough for me to stop tho and i was almost home so I kept going and then all of a sudden a mile from my house it acted as if it didn't want to go. I put my foot on the gas and had it pushed down to the floor and the spedometer just kept going down, then the cars temp went way up in no time and the check engine light started to flash. Thankfully I was almost home, so i pulled over and shut the car off. I popped the hood as a red light popped up that said hot coolant temp. Well i let it cool and walked home. When I came back that evening after a couple hours, I added coolant and water, went to start the car and it just cranked but didn't start. So after sitting and waiting it still woi ldnt start and now its like my battery has completely drained. Even after leaving it on the battery charger, I take it off and it's like it was never on there. I try to start it once or twice and all the lights go dead again. Even after 2 days of me trying to start it, still no start. And no leaks. The radiator is full the overflow tank is where it needs to be, and no leaks coming from anywhere. Now it has all that in it and hasn't been able to get it started to run so I can bleed the valves. Please help. ..
I have a 2001 chev impala 3400 it was cooling great wife drove home from work it sat overnight started fine in the morning was blowing good heat then it started blowing ice cold the hose from the pump is warm the hose to the t stat is cold both have no pressure however if you remove rad cap the coolant will over flow. oil is clean no leaks seen anywhere
+Kylee Sauter First, fill up the radiator and replace the cap, run the car for a short time to warm it up. Turn out the bleeder screws, one on top of the black tube coming out the top of the water pump the other by the thermostat, their 7mm. Wait until fluid comes out to let the air escape. This should give you pressure. If you have heat inside the car for a short time, then it goes away, retry the same process. If this keeps happening, the head gaskets may be blown. The GM 3400 is notorious for this problem. To find out if the system will hold pressure do this test: Fill up the radiator and do a coolant system pressure test. Autozone does the loan a tool program where you buy the tool, use it then return it for a full refund after you're done. Hook it up to where the radiator cap is and pump up the tester. The system should hold @ at least 15 PSI with no pressure drop. If you're unsure on how to do this, most any car repair shop can run this test for fairly cheap. Let me know if you have any further questions and how it turns out. VT247
Ok another thing is I drove it today was blowing cold air temp was around 200-210 shut it off let it sit for about 10-15 mins then drove home an it had heat again then quit again
Try bleeding the system as I mentioned before. May just be low on antifreeze. Or it could be the head gasket. Hopefully it's the easier of the two. VT247
Do a coolant system pressure test. My guess is that there is a leak somewhere. Check the oil, make sure it doesn't look like a milkshake inside. These motors had bad gaskets all around, the intake, timing cover and head gaskets always eventually blow out on these engines. VT247
thanks for great video - i have had this problem for a while now. rough idle, but ONLY when its warm, and as soon as i push the pedal juuuust a bit it runs fine . i have replaced tps and iac , cleaned throotle body, and replaced several vakum hoses , but it stiiiil has a rough idle . COULD it possible be a simple thing as a fuel filter ? i drove it emty for about 5 months ago , and....did it come after that hmmm . i just think that IF it was some fuel problem it shouldn´t run great, but correct me if i´m wrong , could it be a bad intake ? it has some time that noise in idle like a misfire ...like a bad sparkplug wire, but changed em for 6 month ago with plugs . i´m going crazy cause if it a bad intake it should not drive that god. it JUST a rough idle - what am i missing ? please ...please help me if you got a clue
Check fuel pressure, the port to check it is behind the power steering pump on the passenger side near the alternator. Could be a bad fuel pressure regulator, partially clogged fuel filter or a weak pump. Not sure if it's ever had the gaskets replaced, but these engines are horrible about blowing gaskets. If it ever gets hot or to cold, try a coolant pressure test to see if it holds pressure. VT247
@@Vacationtime247 thanks a hole lot for that reply. I will check it later today, as soon as i got that egr valve on again 😡 pain in the but to get to . Noticed that the pipe going from rubber between air filter and throttle body in to the valve cover - dont remember its name BUT it was totally lose in valvecover, MAYBY its that but i dont think it is. Next step is the fuel way. Never ever had a car with so many problems all the time . Especially the fu....ng gearbox ! BUT when it drives im on top off the world. Some cars you just get a feeling for and it aint JUST A CAR you know.
i want to add a note also. flush out the dexcool antifreeze. had to replace a head on a 2004 grand am because the dexcool ate ito the head soo deep it was no good
Rinker262 I got a 3.4 in my Grand Am and it’s been alright so far no issues. I also don’t push the engine so hard either and do all the proper maintenance that’s key.
Have an 2003 Impala 3.4 liter over heating issue ofcourse changed out da thermostat but didnt resolve da problemTried bleeding out da cooling system cause on a youtube video one of da links said da system was pressurized..but as yu xplained in yur video on da 3400 engine there are 2bleeder valve one on gooseneck housing but da other as states on video never should be touched cause it will make yu have an all day headache..lol..but wat if yu never really can get water to come out of da bleedere valves..problem i am having now..so frustrated wit da Impala please help any suggestions are welcomed..thanks
Fill up the radiator and do a coolant pressure test. Could have a leak or a blown gasket. Leaks will be easy to see after being pressurized as water will come out in force. If it doesn't hold pressure and no leak is found the head gasket is probably blown. VT247
Intake pushrods are shorter than the exhaust. You'll know which is which by looking at where the valve goes. If the valve can be seen with the intake manifold off, it's the intake. If you can't see the valve, it's for the exhaust. VT247
You are a sanity saver! I got my '04 Aztek last August as a gift & since February I've had a plethora of issues that I've had to fix. Mostly normal, high-mileage, old-car issues except for the few remaining weird, pull-your-hair-out issues that have had me quite batty. Thanx to this video, as well as comments and replies, I now know what to do. And for the first time in awhile, I am eager and ecstatic to be spending the next couple days in the garage. Thank you so very much for sharing!
Thank you for taking the time to make this video, by 2003 aztek overheated and left me stranded, Now that I have it back in my garage and after watching your video I am confident its the head gasket. I will be watching your other videos and tackling it myself, Thank you again for being the type of person who helps put knowledge like this out there for people like me.
5.17.14. The Dexcool coolant will degrade the L.I.M. Gaskets, along with the head gaskets if the coolant is not completely drained from the system. The engine block has drain plugs for both cylinder banks. The back bank drain plug is located between cylinders 3 & 5, & is difficult to access. People go way too long on the coolant service of the system. 2yr/30k miles is what I go. Also the EGR passage port in the upper intake manifold clogs up with carbon, causing a poor or stalling idle. I pulled my engines L.I.M. Off at 82k miles and the L.I.M. Gaskets were just showing slight signs of degrading, not leaking yet. I decided to pull the heads off to inspect the head gaskets. I found that the Dexcool was degrading the head gasket where the opening for the coolant in the block met the opening in the head! It was not leaking yet, but would have in time! I use Fel-Pro metal framed L.I.M. Gaskets & SD head gaskets. Another source of oil leaking is the oil pump drive O-ring located near the flywheel end of the block.
Steven Sapyak this guy hit it dead on!
What kinda coolant you use I use 50/50 universal antifreeze
I got lucky. Previous owner changed intake gaskets and did green coolant. Still going (knock on wood)
Yep you hit it right on the head! The previous owner of my 04 grand am 3.4 had changed over from the orange dexcool to the green and saved all the gaskets that way! I got lucky, unfortunately the transmission has issues after it warms up from freeway speeds. When i come to a stop it shifts hard into the next gear all the way to fourth, so i feather it as well as power shift to shift it sooner so it lands a softer shift.
@@johnanderson5500 if you can, hook up a scantool and monior data, see if the mass air readings and everything is correct. Shift strategy ,etc use a lot of Inputs
the 3.1l didn't so much have head gasket issues but it dose have intake gasket issues. I hade to replace the lower intake gasket on my 91 Pontiac 6000. he'll of a motor though. ran the shit out if it everyday and when I traded it in it had 315,000 miles on it and it still ran like a top
I have a 1999 Silhouette with 300,000 on the vehicle, replaced trans and engine around 150,000. I intend to drive it until I replace it with a flying saucer :) . I made a modification to the coils and wiring to make it easier to access. I straightened the L-shaped aluminum mount upon which the coils and ignition module rest, then mounted them on top of the intake manifold. It still clears the hood, but makes it much easier to get all those parts in case the coils or module fail. I came about this because a had a no start, that seemed as if it was an ignition module, but turned out it was a broken wire from the crankshaft position sensor. I am prepared to fix this on the roadside, so I try to keep spares with me for things that often break.
That is one of the best videos I've seen , lots of good info . Thanks for sharing it .
TheReaper!
I wish I saw this before I changed my thermostat and water pump. Thank u
You basicly named like 3 issues im currently dealing with. And thanks to you i have a better understanding how i can fix them. Ty
you are also knowledgable on these engines. i did my head gasket job back in 2010 70k and an in car partial rebuild of my 160k trans. (clutch pack, sun gear, 4th gear, chain, bands) needed for a failed sun gear and work clutch packs)
when i used to put my car in gear, there would be a slap - turns out there also was no hardened
chain in the trans, and it stretched, and caused that annoying slap.
anywho, something worth mentioning is that GM recommends to keep the surge tanks filled up to full hot when the car is cold. this is extra insurance against the surge hose sucking in air on a slow coolant leak and causing hot spots that can damage the head gaskets.
i had my 3400 in my Chevy Venture van since new in 2002 and only have ~185,000 as of May 29, 2020
i have the 3400 when its idleing in drive it gets hot and than goes back to the cold side but it dont over heat it actually runs goood and another thing the code p0401 keeps poping up i changed the egr valve and it stilll pops up thanks alot besafe always have a great beautyful day
Do a coolant system pressure test to check for any leaks in the system. Could just need the air bled out and coolant topped off. The EGR 0401 code is likely carbon build up in the passages. Take off the throttle body and EGR. Run a hard wire down the port and clean it up, suck out the carbon that comes down through the intake.
VT247
it does leak a little coolant but im not sure if thats it and egr valve im trying to do that im to sure how but ill try thanks
My 3400 ran hot for 2 years. I changed the thermostat now its perfect
Thank you so much for this through break down. I wish I saw this video a long time ago. Would have saved me so much money, time, and heartache
Excellent Video! More information than I expected. Thank you,
Excellent help Video. It solved my Headache I haave had for A few years. Thanks.
I ran a direct wire and removed my thermostat put some blue devil and it's been running good for 2 years with no engine problems
2000 chevy malibu Ls 3100v6
helo… what do you mean by direct wire .. I have a 2001 3.4 L Impala and troubles with overheating ..can you help me with that ?
@@Shellie-5 ty Cathy.. hope that will fix it...
@@Shellie-5 was your temp gauge reading normally before replacing the sensor? Or was it always reading all the way cold or hot?
Jw, I think I'm having the same issue with my van...
@@Shellie-5 is that the sensor right at the thermostat neck?
Here's one for you:
2000 Silhouette 3.4 was overheating. Replaced t-stat because it was sticking. Purged air using a hose tee on the heater hoses and raising it above the rest of the system. Purge, fill, repeat until there was no air left to purge. Both fans operating. No white or otherwise unusual exhaust smoke.
Engine ran great, heater was hot, temp gauge fluctuated but stayed generally in the middle. Took it on the highway for about 5 miles at 50-55 mph and began to hit the red zone. Tried using 3rd gear to accelerate coolant flow but that didn't seem to have an effect. Engine started to lose power as I pulled off highway. Slowly opened hose tee to see if there was air in there again, and there was a lot. Released steam slowly for about 5 minutes, then started it back up and drove it home. Had to release steam two more times to make it home.
Possible diagnoses:
1.) Head gasket dumping exhaust into the coolant and pressurizing it, but if that were true wouldn't there be white exhaust smoke?
2.) Water pump not moving coolant fast enough and it's boiling.
3.) Radiator plugged with rust and Dex-Kill goo.
4.) I didn't really get all the air out.
Pretty sure it's a blown head gasket. These engines are known for gasket failures. Might try a coolant system pressure test and see if it holds pressure. Could try a chemical test and check for exhaust gases in the coolant. It's a blue dye that changes color in the presence of exhaust gases.
If you do have to fix the head gaskets, do the entire engine, timing cover, head and intake. They all go out eventually on these motors.
VT247
@@Vacationtime247 Forgot to say I did go to AutoZone and rent a pressure test kit. It held 16 psi as long as I could hold on the GM cap that didn't fit perfectly. A full 60 seconds maybe; didn't get a chance to fix the cap issue. I was also thinking of the chemical test.
If it's a head gasket, I don't have the time or space, and we'll just hock the van on craigslist and try and get $400 for it.
I'm the kind of guy who buys cars before I go to RUclips to find out that there're entire videos dedicated to the stupid problems that these engines have.
I have a 3.4 buick rendezvous, hopefully it'll be alright lol
Lincolnator i had the same car it overheating problem made me crazy
Rodrigo Batista How many miles did your Rendezvous have? Mine currently has 211k miles and no overheating issue *at least not yet anyway*
Mine had 134.000 i had to get rid of the car for 1100 dollars you are lucky with this milage keeps until it drops.
Rodrigo Batista dang, that is really low miles for it to overheat. i'm sorry about that, i'm sure you were upset. and i know i've heard and read a lot about these cars overheating, electrical issues, and rear end noise. luckily i have none of those besides the rear end noise (going over bumps) other than that it seems to ride nice. guess it's the chance you're taking whenever you buy a car whether it's new or used
Wow I have been messing with my 97 Venture on and off forever! When it runs...IT RUNS!....I learned SO much from this one video about my Mertha...Do you recommend any sources that are HARD CORE Venture specific? New tuck is toooo expensive right now!
02 Venture van 3.4 temp gauge straight up 12:00 should be about 212 deg F. T stat is set for 195 full open . Each increment is about 7 deg first mark is 156 f. Low speed fans on at 220 f to 230 both fans on at AC on or above 230. Red line starts at 254 f Top red line is 268. always use factory OEM T Stat. Wide swings are normal but listen for fans and when ideling on hot days it may go to 3to 4 hash marks past 12 oclock .. I use Prestone , dont mix with Dexcool . Purge the dexcool completely and replace , change about 2 yrs Good luck
Mine tends to take forever before the needle moves into the normal range. Then if I am stuck in traffic on a hot day, the needle moves up quickly to near the red. I suspect a partially stuck thermostat in the open position, but I stripped the bolt so I will not be replacing it. Or it could be just bad design. Since I got this van as a gift, I don't know what it was like when it was new. Every car I have ever driven, the needle of the temp gauge is rock steady once the engine is warm. This one seems to fluctuate wildly.
@@lwh7301 Mine fluctuates quite a bit as well . Take note of my previous post as to temp increments . the fans should come on as I said . Near the RED ouch it can get close but should shut down to 212 straight up once the 2fans cick on . You must find a way to change to an OEM t Stat they are more expensive but if you dont want intake leaks or Headgasket repair you need to address it unless you drive it into the ground . the cooling systems on these vehicles are problematic if you dont keep and eye on them .
@@oldtimedrumcorps The fans do come on, but seeing the needle go up causes anxiety when I am stuck in traffic. Once the van starts moving, the needle drops back down. I doubt the thermostat was ever changed. As you know, it's not the easiest thing to do. I got a Stant thermostat 3 years ago, but stripped the bolt, so I never was able to replace it. The van has over 200K miles, and drives great. I use it only when I need to haul big items. So I may just leave it the way it is, and the van never over-heated, just gave me a scare since I have never seen temp gauges move like that. And if it blows a gasket in the future, then I will surrender it to California for $1500.
@@lwh7301 is the coolant green or brown Try to not mix . dexcool is brown ish leave it and only top with dex cool. Still Dexcool is a problem if air is introduced in the coolant . I would put in a new temp sensor they are not expensive . Sounds like rather than getting too involved you might just run it as long as it hasnt given up the ghost Mine will run up high I put it in park if i sit for a long time . It wll drop about 30deg when if both fans kick on . Hers some fun facts . the first has mark at cool is 153then each is 7deg more at top dead its approx 212 degf in the summer it will be around 212 and move up to as much as 235 before both fans come on it then drops quickly or if i resume driving . BTW I get antsy when it gets up there so i dont like to sit forever at the star bucks window . Good luck
@@oldtimedrumcorps It was already green when I got the van. Then I flushed it and put in green, after reading about Dexcool.
Thanks for the great video.. at 2:05, when you're pointing out the intake temperature air sensor, there is a small 90 degree hose that also goes into the intake and is followed into a hole in the engine around back. it's fairly short, about 12 - 14 inches. Do you know what it's called and what it's for? I broke mine while removing the intake in the middle of winter and it was fairly brittle. I spliced it back together with a flexible clear braided PVC hose until I can find a part number. I'm hoping it's not damaging because it's also PVC. but I'm not driving the vehicle at the moment until I'm sure. Thanks for your help.
+Rahim D. That tube is for crankcase fumes to be recirculated back through the engine. Not sure if it's got an exact name. PCV crossover tube. As long as it has a good seal and doesn't have any vacuum leaks it's good. Might have to get a replacement from a junkyard.
VT247
Ahh that makes sense... Thank so much
Seeing that it has an iron block(if I'm not mistaken).. As long as you change fluids religiously and take good care of the top portion of the engine(all aluminum) it has the capacity to go 300,000 miles or more..
Thank you so much i have an 2003 alero & im dealing with this same problem again it ran hot but instead of getting a regular 3400 motor head i got an super charge. & it started over heating & misfiring so when i pour water into it its comes out the motor head.
Wonder if one or more of the head bolts got stripped out. But the head has to mate with the block right or else it will certainly spew water all over. The GM 3400's had problem with their gaskets. Best to rebuild the entire thing with new gaskets if your doing one. Because eventually, the head, timing cover and intake gasket will all eventually leak.
VT247
Take it for what it's worth: I got my 04 Venture with almost 50k miles on it. Now it's at 190k and the only non-routine things I've ever had to fix were fuel pump @140k and water pump @ 175k. This is the best car I've ever had. I also have an Aztek currently with 140k on it. In 60k miles I've changed water pump and nothing else.
Bought a Impala new in 2000. Highly maintained it. 130,000. Both heads cracked. New loaded GM heads were a good deal. Lucky the colant leaked into the combustion chamber.no Water in the oil. Took me 3 days to install both heads. Getting slower at 58 years old.
No kidding. Not getting any younger myself. Used to be able to work all night on a car then wake up and do it all over again. Now, the ol' back makes me pay for any work done the day before. lol
VT247
58 is getting old! 🤔🙄🤭 I turned 80 last week. I bought an 06 Buick Terraza with 3.5 cheap because it started to overheat. I tried everything short of gaskets. Nothing worked. No cream on rad cap or dipstick, or oil on surface of coolant. There's combustion gas in cooling system, so I am now half way to complete. Got FelPro gasket set. In Missouri it's a bit warm to work on cars outside. My heads are not cracked or warped, so almost ready to put everything back together. I don't think I'll be able to do this many more years. Most of 3 days so far. Hope to drive it within a week.
I push coolant into the radiator with the coolant exchanger (under light pressure) till coolant comes out of both bleeders. Found it the fastest way to get air out. I am at the point I have to do the gaskets though
Do all the gaskets while you're in there. Like the timing chain gasket as well.
VT247
Yep. Me too. To hell with Chevy Venture and the 3400 v6 engine. Everything said here was spot on. Be prepared for over heat problems and head gasket jobs. Iam junking mine. Just blew gaskets for the 2nd time in 2 years. Stalled on me about 5o ft from my house at a busy intersection. Had hazards on. Still got side swiped. Tore the whole passenger side to hell.
I have an 03 silhouette. Last year i did a head gasket replacment due to engine over heating. Our one means of transportation. Ran top notch till it all of a sudden threw a po303 code. Cylinder three multiple Misfire. Spark pkug and wires and coils all check out ok. Issue is when you try to accelerate it tries to bog down. Check engine light startd to flash. Once gas pedal is released engine light eventually goes back to solid on. Checked ohm reading on the fuel injectors and got 11.6 on #3 and #1. Still main mode if transportation so any and all feedback is welcome. Thanks
Here's what I'd check if it were mine. Getting to the injectors can be difficult. Check each injector with a noid light, make sure it's getting power. While it's dark outside, mist water around all the area's of the #3 cylinder and make double sure it's not the spark system. Had coils that look good but are cracked and will throw blue sparks if there is a mist of water around it, causing it to misfire. Might swap the coil pack and wire to another cylinder and see if the misfire moves. Could try tapping on the #3 injector to see if the idle changes. Just a few suggestions.
VT247
Vacationtime247 thanks. I tried swapping coils and it still had same code. Its hard to grt to the injectors like you said so how would you suggest reaching them with plenum on?
at idle there really is not much of a mis that is noticeable. But I will try the water trick to see if spark is jumping out of #3 coil area. Stay tuned...
04 rendezvous overheats, blowing cold air in the cabin and smell a lil burnt sometimes from the engine.
Very informative, thank you for taking the time to make this video. I have a question about my 2000 3.4l Impala. I'm having a problem with the bank 1 sensor 1 o2 sensor. The scan tool I'm using shows a negative reading during live data. I have another Impala (2003) 3.8l and it says the same thing on sensor 1 bank 1. I was just wondering if it's a common issue or if I'm doing something wrong. I've replaced the sensors, I've used cheap o2 sensors and I've used expensive ones but it still doesn't help.
thanks for all the information...greatly appreciated...keep em coming......you the man...
Thank you for all the info. I have a 2003 olds alero with the 3400 and it has been overheating but it also has been throttleing on it own. I will be going 45 let off the gas and it stays at 45. So my wonderful mechanic first had me buy a water pump then the temp sensor and he was sending me to get a thermostat when i noticed that neither of tye fans where running and it was well above temp at this point. So i check fuses and cleaned relays but fans still dont work. What do u think. And i checked the oil cap and dip stick and do not see any white residue nor can i spot a leak when u showed to look. I truly appreciate your help.
Bleed the system of air. If it runs fine for a while then overheats along with again having air in the system, it's probably a bad head gasket. Might try a system pressure test to confirm. As far as the staying at the same speed, check for vacuum leaks and if the throttle body is closing all the way. To test if the fans work, unplug the temp sensor and they should come on, but this will trigger a code. Yet, it's a quick easy way to tell if the fans are working.
VT247
Vacationtime247 WOW man I didnt really think you would respond. I wasnt sure like how old your stuff was. I really appreciate it. I think my biggest problem in the situation was the guy who I thought was a mechanic but it turns out he is good and putting on new parts which if i had a garage full of tools and RUclips i could probably do. So today an old newer friend of mine called me and i totally forgot he us a certified mechanic and works at a shop. So he looked it over today and tomorrow he is going to take it and fix all this crap. I will pass on your info. He did say that i definitely have to buy a tensioner pulley because he could actually see it moving around and its possible that was causeing the throttle issue. And once again I really appreciate it it's good to know that I can reach out to someone if i have anymore issues.
I've got a heap of a 1997 oldsmobile HELL-OH-ET with the 3400 engine and it is leaking coolant from the passenger side of the engine . I think it is coming out somewhere by the water pump or tensioner pulley assembly but i can't see for sure . I do know it's not coming from the radiator or the hoses. It's almost seeming to be accumulating on the face of the water pump pulley and getting spattered on to the radiator and the control arm etc , but it seems like it's barely accumulating when I'm parked and the engine is idling. I believe driving is when it leaks the worst due to there being alot of coolant in the areas i specified when i popped the hood to inspect the sweet coolant smell i smelt when we were driving it home . There is no coolant in the oil and no bubbles in the reservoir and the heater works great , i just replaced the temp. Control sensor and bled the system properly . If you have any suggestions my email is canjojohn02@gmail.com and i would appreciate any suggestions at all . Thank you , sincerely ,Rod
Thank you. This video was very helpful. I'm going to try your method on riding the over heating problem. Hopefully it clears the probpem. Again Thank you
I have a 2000 Impala w/ 3.4 and it seems work as far as morning startup and running the heater, however when you look at the temp gauge it will be 165 or so and only one time I put coolant in was when we found a cut or bad area to the overflow eank at the radiator, we cut off the bad area and replaced no more leak. But yesterday I had to make a road trip of about 60 miles oneway going down know problem 59 outside temp, coming back 72 outside, about 175 on temp gauge and when we got 12 miles from home the message center flashed LOW COOLANT LEVEL, I pulled off the road and checked coolant tank and it was 4 or 5 in down from top, both hoses had pressure and never got to midrange temp untill I got home. I checked levels the next day and everything was fine. Now the Service Engine light in the message center is always on, been reset I dont know how many times, got it on a big computer and the only thing he could find was a BCM maybe bad or what have you, but the system itself is fine. Would the BCM cause something like I mentioned ??? The car sit for 2 years, because the lady bought a new car (traveling nurse) The gas cap doesnt stay tight, the radiator cap (looks) like it could be replaced (but not leaking that I know of) As far as water pump or thermostat I dont have a clue. Im disabled and I needed a car and was given this one, but I cant afford any big repairs. Can you PLEASE HELP ME ??? Thanks
There may be a coolant level sensor on the car, may be faulty. Also try adding fluid all the way up and then bleed the air out of the system when the car is at operating temp. There should be two bleeders. One on top of the water pump, the other on top of the water neck outlet by the thermostat.
VT247
On my Venture, the coolant level sensor is on the end of the radiator below the radiator cap. If the coolant level is 4 or 5 inches down, then the coolant level sensor should be signalling low level, which in your case it did. I recommend using a spill-free funnel for bleeding the air out of the cooling system. That's what I use and it works great. You should do a coolant pressure test though to check for leaks. You should also check to make sure the head gasket isn't blown. Use a combustion leak tester to determine if there's exhaust in your cooling system. Also make sure there's no oil mixed with your coolant or coolant mixed with your oil. When you fill up your radiator, also fill up the coolant reservoir to the hot level line. GM recommends filling it to the hot level line while the engine is cold to ensure no air gets drawn into the system.
I have a 2002 Chevrolet impala 3.4L that overheats when going up mountainous roads during summer. Coolant is level, fans work, thermostat works as it should, new coolant pump, and just has coolant system pressure test done but can't figure out the problem. Live in Southwest Virginia
Sounds like you've covered all your bases. When you say it overheats, does it puke out the overflow tank? If not, then it may just be getting hot but not necessarily overheating. Only other suggestion would be to make sure there aren't any blockages in front of the radiator. May try pressure washing to clear the venting fins.
VT247
Our mechanic said the aftermarket oem quality water pumps are garbage on these engines. We had the same problem. The intake was leaking and the gaskets were replaced. Then the Gates water pump failed after just one year. The water pump caused overheating again, and it blew a head gasket. The top end was rebuilt, and a GM Goodwrench water pump installed. Since then no problems, and that was five years ago.
Thank you so much, I will do that today. Also I was told to loosen header exhaust bolts that converters was bad for going bad on those, I did check the exhaust and could not hardly feel much exhaust. So I'm guessing I will be trying both today. I will let you know how it turns out, thank you agian car friend.
I've cut out a section just behind the cat converter and then used a hammer and pry bar to bust up the material inside. Then blow it out by starting the car a few times. If after cleaning out the cat, the secondary O2 sensor reads low or wrong voltage, add in a spark plug non fouler to the end of the secondary O2 sensor. Drill out the inside of the non fouler so the O2 sensor screws on inside. Will keep the code from setting.
VT247
right on thanks guys! no wonder it wouldn't take more than like a quart of water after it vented at least a gallon into the overflow. it has been sitting since my last post and for the record Vacationtime knows his stuff. Nobody wants to accept that their car has blown a gasket but that ended up being the case with this montana as well. Another one bites the dust! may as well count on any of these v6's to blow at some point and if you get 200kmi+ out of one, consider yourself good a PM tech. anybody interested in picking up this blown out soccer mom/ G ride for a steal of a deal in UT let me know
Mine has had the intake manifold and head gaskets redone. Not smoking and no coolant in oil. Also it's not running hot but I am losing coolant. I can fill up the radiator and start it up and drive it for 15-20 minutes and my low coolant light will come on. I've also changed that sensor as well. Heat works pretty constant. I also have virtually no pressure in the system as I can drive the car like I said and remove radiator cap no problem. Thoughts?
Do a coolant system pressure test. They rent the tool at Autozone. Basically you hook it up and pump up the connector. It applies pressure to the system. Make sure the pressure doesn't drop rapidly. If it does, check for leaks or sounds.
VT247
I don't know why I can't see my previous message. Anyway, what is the cable that you touch with your finger for in the min. 5:27? in my 2002 venture the right side cable is loose and I can't see the other part, which has a white plastic part. thanks
Temp is right in the middle. 4t65e seems to desire a few degrees less temp; Ive got mercon atf. ( The normal 2005 atuff) My 4t65e hard shifts (thumps) at temp.
So, Q: Any guess? Maybe it is an ATF viscosity at temp? How can I get a few degrees less temp? Maybe some ATF thickener like STP.
I am thinking of using 160 stat and hard wiring radiator fan to 100%. Id really like to stop the trans to stop slaming shifts. Kinda think that holding temp at 160 will fix it. I do appreciate your thoughts! Old Timer Richard.
Check for vacuum leaks. Had this problem in the past with bad shifts and a leaking vacuum hose. Might check the mass air flow sensor too.
VT247
@@Vacationtime247 I suspect I had an air lock in cooling system. The 4t65e needs the correct temp. to function well due to its advancing age.
Getting the air out w the bleed screws looks like all it needed.
If troubles are marginal, I will add an aft market trans cooler.
I do think my valve body needs care due to wear and blow by.
Theory is the cooler will keep the viscosity up by preventing excess thinning of atf fluid.
Thanks for your knowledge.
My fans were just broken I just wired a speaker wire to the sensor and to the fan fuse. They kicked right back on.
Glad that worked! Sometimes it’s just something easy.
VT247
I'm working on a friend's '04 Impala that has random overheating issues. There's no bubbles coming out of the radiator when running, so I was hoping it wasn't the head gasket. I replaced a leaking water pump and thermostat and bled out the system; all to no avail. I'm not sure if the leaking caused the overheating or what, but it's beyond obvious that GM didn't put any stock in the engineering or longevity of these engines and the cars they put them into. They earned that bankruptcy in 2009, and it's a tragedy they still have customers after the garbage they sold; but people are idiots and blindly advocate companies that don't give a shit about anything but their bottom line, so go figure...
Anywho, I have to commend you on your obvious patience and (maybe) love for these things and defending the 3400. I disagree entirely that they're worth saving because of the inherent flaws and absolute lack of logic in assembly, but you see things differently and that's cool. The Impala I opened with barely has 117k miles on it and is pulling the overheating shit while other systems are failing, so all I want to do is use it as a four-wheeled wrecking ball until it burns (despite how much I hate waste). But you're inspiring me to give it another chance in trying to fix it that will end in my fiery rage :')
Do a coolant system pressure test and see if it holds pressure, autozone does the loan a tool to try it. The GM gaskets that they assembled these engines with were absolute garbage. If it does happen to be the head gasket, check out my video's on how to do a repair / replacement. Currently have 2 of these engines each in '01 Azteks and all the gaskets have been changed in both, intake, head and timing cover. If you do happen to do the head gaskets, it's worth it to go ahead and do the timing cover gasket too. Best of luck.
VT247
I sympathize with your frustration. But I would like to respectfully offer an alternative.
Spinning a wrench is therapy for me and something I love doing, so I try to just accept the flaws of each engine rather than getting too frustrated at them. There's a lot of satisfaction in getting an older car to run well, and I know it will always cost some money and lots of time to get it there, not to mention a few skinned knuckles and brushing grit out of my hair for a week. Overall, I just find it better to get a list of what usually needs replaced on a certain brand of car or engine and plan on replacing that list systematically. I then reserve my frustration for politics! The satisfying thing is that when I have to do head gaskets, I get to save $1,000 or more by doing myself, and I get 10-20 hours of therapy while I do, and it is me against the world ... I either do a good job and get a good car in the end, or I screw up and have to do something over or junk the car. Fair enough--that is part of the therapy as far as I am concerned.
Each engine has its flaws and weaknesses, and it is true for all engines. Even workhorses like Toyotas. My so called "run forever" Corollas leak oil (rear mains at 130,000 and chain tensioners at 100,000), and both needed intake manifold and valve cover gaskets before 100,000 due to hardening of the original neoprene gaskets. My 2003 Corolla ate oil like crazy by 90,000 miles despite having changed the oil religiously and having run only synthetic oil for the life of the car. It still ran well at 170,000 when it slammed into a telephone pole in an ice storm and was totalled, but I had to nurse it along for 80,000 miles of oil level checking. My Subarus have needed timing belts every 100,000, and usually a set of head gaskets as well, and all of my cars have needed struts by 150,000 miles.
So with the GM 3400 engine, we know it will need upper and lower intake and head gaskets by 100,000 original miles, period. But then it is good for 100,000 miles more or longer if you use better gaskets. Even the number of things to take off isn't much different from other engines... wiring, fuel rail, etc. And thankfully, you don't mess with the timing like you do with all overhead cam engines...
That's true. Most engines will need fixed at around 100k miles to some degree. The 3400's use a timing chain and no type of fancy overhead valve assembly. That is nice considering they usually last for the life of the engine. Never was a fan of timing belts, like Dodge and other manufacturers use. If it's an interference engine, and most are anymore, when the timing belt breaks, you're getting valves, pistons, possible head or just junk the entire motor.
Best motor I've ever had and will still attest to this day was virtually indestructible is the 250 inline 6 put in the 1970 Chevy C10 pickup with the 3 on the tree manual trans. Beat the living crap out of that motor. Hauling loads in the bed that would nearly drag the bumper on the ground was never a problem. Manual door locks, manual trans, manual windows, no factory stereo, manual steering it was so simple nothing ever broke.
VT247
I tell you man those engines are a piece of work ,I drive a 03 Chevy venture sometimes drive me crazy
No doubt. If you get a vehicle with one of these engines, plan on replacing all the gaskets.
VT247
Vacationtime247 Got a 3.4 V6 in my Grand Am no issues has 140,000 you guys most not know how to look after your motors
Thank you for the information. I have a question on my 2004 impala 3.4 engine. Besides the loss of antifreeze I recently noticed a large loss of oil that I had to add, when this engine previously had no oil usage problems. Can a bad intake gasket cause this? I do suspect a bad head gasket though.
I know this video is years old, but maybe someone can help. 2000 silhouette. The low coolant light goes on and off but there's plenty in the reservoir and radiator. It wants to overheat when idle. No bubbles in the coolant reservoir. No white or milky junk in the oil or the cap. No white exhaust. This lead me to think the gaskets are fine. I'm thinking the thermostat stick closed or coolant temperature gauge might need to be replaced, or maybe there is a clog in the coolant system somewhere? Now I'm wondering if I missed something or there could be a different issue because you state that the thermostat going out isn't all that common. Is there anything else I should be looking for?
Thank you, this has helped me a lot.
Thank you for sharing ....My friend just baught one i can hear loud ticking. As a friend ill share the info......A viewer from MEXICO......
My 2000 Grand Am SE is ticking also the code reader read misfire
I was changing the coolant temperature sensor in my 2001 malibu and the part that it screws into cracked around the sensor was wondering what the part name is it screws into
Whats is the normal operating range on the temperature gauge. I am usually at the 11 oclock and 12 oclock in city driving. But around 1 on highway driving. Thank you for any information
What is that hose you pointed to saying it can cause a vacuum leak
Not sure what the name of it is. There’s a rubber grommet that the vacuum tubing goes into that fastens to the upper intake. Make sure it is fully seated and secure. Might have to remove the metal throttle cable bracket to see or fix though.
VT247
I have to say that these engines are bad for the gaskets, but if u replace the gaskets and catch it way before it causes a problem in the lubrication system, these engines can be rather dependable. I have a 2000 monte carlo replaced the gaskets, and its got near 400,000 on it, the transmission went down about 313.000 it's got a little valve tick, but it's not no big deal to me, but these engines are pretty decent if the gasket job is caught in time. Thanks for the video!
I build and mod these engines i have several grand ams i like the car, but i tell every who repairs or is trying to rebuild the 3400 or even the 3100 engine is never go cheap on the gaskets especially the lower intake gaskets i always get the metal gaskets they last forever and also they dont restrict air flow like the plastic gaskets do.
Why does my "97" 3.1 litre chevy run hot? I have changed the relays fan blade, fan motor, flushed the radiator, thermostat and water pump. My car had the head gaskets replaced with alluminum at 134.
RUclips notifications of comments aren't showing up like they used to. If this is still an issue, try a coolant system pressure test to see if it holds pressure. They are known to have bad gaskets such as the timing cover, intake and head gaskets.
VT247
@@Vacationtime247 I appreciate your help. My car holds anti freeze would you still presume a pressure link still exists?
I inheirited my mother's 03 rendezvos with the 3400 engine. It's never had anything done to it engine wise, just a ton of front brakes and wheel bearings. When I was bringing it home, the temp gauge flew up to hot and the bell went off and before I could pull over it dropped back down into the normal zone. coolant was low in the radiator about a quart and the overflow was down to where the hose wasn't in the fluid. I don't have any sign of coolant in the oil or any sign that I can find of coolant leak. I've seen a lot of videos on burping the cooling system. I'm hesitant to start tearing it apart without learning more. I also have no heat in the cabin, but tho the engine is at normal operating temp. The blower works on 1,2,4, and 5 and I've seen several people on here saying that heater controls have bad connections resulting in burned off contacts and there is a funny smell, kinda like something is burning. Got any advice for me? Or do you wanna buy a rendezvous cheap? lol
Fill the radiator and reservoir up with fluid with engine cool. Start the motor and bring to operating temp. Turn out the 7mm bolt on top of the coolant neck or on top of the water pump (that black metal pipe). Let the air bleed out and tighten the screw. That should let the heater blow warm air.
VT247
I have a 2002 Impala 3.4 and it is overheating... The water pump and hoses have been replaced, and it seems like the radiator is pretty new, as well. After replacing the water pump, and driving it around the block, it was overheating again and hissing to the drivers side of the engine near/in the vicinity of the air filter hose; the end that is connected to the engine, near the thermostat... Help?
Sounds like a blown intake or head gasket. These engines are known to blow the factory gaskets. Best to do both at the same time while it's being worked on. Do a coolant system pressure test to confirm.
VT247
Thank you. How much ya think the gaskets and RTV and whatever else is needed would cost? Worse case scenario? I know the labor is gonna be a bitch.... :(
I'm guessing around $150 for the gaskets, RTV and other parts. Labor depends on who and where you have it done. It's not a really hard job to do, just takes a while.
VT247
Dude this engine is both one of the most fun I've had with a car when they work good to one of the most mechanically and financially demanding engines I've ever had. My 03 grand am gt jumped time on the first engine and overheated with a new thermostat, and full radiator & new oil. Nearly set the thing on fire with how angry I was.
Best thing to do with these engines is to completely rebuild them with all new gaskets, Head, Intake & timing chain cover. They all eventually fail. Didn't have a coolant pressure system tester until buying one of the vehicles these engines come in. lol
VT247
Thanks for the help mine just overheated today is there an easy way for me to test the thermostat to make sure it's not stuck?
If after running for a while, one radiator hose is very hot and the car overheats but the other hose is cool, the thermostat is probably stuck provided it has sufficient coolant. These engines tend to have issues with the blown gaskets, intake, head and timing cover. A coolant pressure test would be helpful too to find any leaks and see if it holds pressure.
VT247
I purchased an 01 Aztek GT in 2002 and really enjoy this vehicle. Over the last twelve years, the intake manifold and head gaskets have been replaced once.
I have a problem with the engine temperature gauge showing an increase in coolant temperature when I'm in city driving conditons. At the same time, the automatic transmission starts "hard" shifting. The cooling fans do not run unless the AC is turned "ON". How do I make the cooling fans turn "ON" without running the AC?
The coolant fans will only turn on when the temp gauge gets pretty high unless you turn on the A/C. You could get a tuner program and reprogram it that way, otherwise it is factory set. Mine does the same thing.
VT247
Vacationtime247 Hi, Thanks for the video. I have an 03 Malibu with a 3100 engine. It overheats. I unplugged the coolant sensor temperature and the fans come on. The fans don't come on otherwise. What would you look at next if I know that unplugging the sensor turns the fans on high, fans work and fuse it good? I have not tried to bleed the air out of the cooling system yet because the fans don't come on I figure it is electrical. I have seen suggestions of a secondary fan control however I am not sure how they are wired in or if this is the fix needed. Do you have any feedback on this?
www.autozone.com/productComparisons/productComparison.jsp?originalUrl=%2Fcooling-heating-and-climate-control%2Felectric-fan-thermostat%2Fchevrolet%2Fmalibu%2F2003%2F6-cylinders-j-3-1l-sfi-ohv%3F
Thank you,
Matt
Vacationtime247
Situation- 2001 Aztek runs perfect at highway speed, temp gauge reads normal. Then I slow down for city driving and the temp gauge registers a higher temp (needle moves up "1" mark below the overheat range). At the same time, the computer instructs the transmission to raise line pressure and the transmission begins harsh shifting. I parked the Aztek in the driveway with the motor running and opened the hood. The cooling fans were not running. I measured the coolant temp with an infrared scanner and watched as the temp reached 237 F on the scanner. The cooling fans started running on low speed at 237 F and then stopped (10 seconds). I unplugged the temp sensor and both fans ran on high speed.
Why does the computer tell the transmission to go into "limp" mode and start harsh shifting? Is there a sensor that is picking up bad information? The vehicle runs great in cooler weather.
+alvinspmn The transmission is trying to save itself from burning up, this is why it goes into 'limp' mode. Do a pressure test of the coolant system and check for leak down. If it does leak down, listen for a hiss or water / coolant coming out. Sorry to say this, but these 3400 engines have a bad reputation for blown head gaskets.
VT247
Hey my buddy replaced his thermostat in his overheating 2001 Buick century. Now when he tries to start it up it cranks but won't actually start then possibly a back fire or burp.. what should I look at first to address this? Probably occurred during poor mechanic work
Sounds like a wire or plug in didn’t get put back. Look for loose or broken connectors.
VT247
I'm currently having an issue with my 2004 Chevy venture it over heats and goes from warn to hot when u get up to a certain speed
Check your fans. While it's idling in park, turn on your ac and see if your fans kick on. If they don't you have a problem some where. I had that problem which was the ac relay which actually poped and prevented my car from starting because it blew a fuse that shares the pcm with the ac. I own a 2004 Pontiac Grand Am SE1 3.4L but these Pontiacs are almost the same if it has the same engine. Mind you i say "Almost" the same. Anyway what i did was pull out the relay block in the fuse box, and replace the blown fuse i had, then manually hooked both fans up to a switch to the battery. This means i can turns the fans on anytime, but i don't have ac. Hope this helped. By the way if you're ac doesn't work and you don't care you can eliminate the ac radiator in front of your actual radiator for more air flow to keep it cool. Mine was already empty so i cut it off. But if its full your supposed to have it professionally emptied.
Dex cool antifreeze causes the intake manifold leaks
Research shows it's to air mixing with Dexcool that causes issues. Fill the overflow bottle to the HOT mark and keep it there so engine sucks no air.
glad i dont have to replace head gasket 192,000 miles still going strong 99 olds silhouette
thank u for responding so far I've taken it to several shops no one knows so been trying to research why I would have heat, air, holds pressure,no visible leaks, no coolant lost, no milky oil on dip stick did notice little condensation under the oil cap but that's normal right? no unusual colored smoke or consistency coming from tailpipe, fans working no pully loose, belt look fine however at start up does have fume like smell by the way it's a 3.6liter
+drae allen It's possible that the thermostat needs changed out. If it's stuck open it would cause overcooling in most situations. My first guess is that a gasket might be leaking internally because the gaskets on these engines from the factory weren't good.
VT247
Dorman heater pipe- would you happen to know what that is? I have a 2000 pontiac grand am gt (black lol) it wouldnt let me leave a pic in the comments but i was wondering if it needed an O ring or somthin cuz i just push it in but it doesnt stay good enough then it starts leaking coolent. It looks like you just push it in but idk if i was missing a ring or somthin cuz it still will start to leak coolent.
Very appreciated if you can help
I'm having some serious issues with my girl. SHE'S A 2001PONTIAC GRAND AM SE1 WITH THE 3400 V6 VIN#E SHES got about 167000 miles on her. All the upper intake manifold gaskets and hoses were changed out by the previous owners mechanic as the were leaking about 1 year ago I was driving, pulling into a parking lot. She started sputtering like she was out of gas, (which couldve been possible due to a problem with my fuel gauge stuck on empty no matter the amount of gas in the tank) so luckily gas station was next door. Put 4 gallons of gas in her tank. At times like this as soon as I put gas in her tank she started right back up. Except this time... So far I have released the pressure in the fuel rail, turned key on a couple times. I can hear the fuel pump run. First few times I did this pressure was not there. So I replaced fuel filter. Pressure returned in the fuel rail. I'm not sure what the exact pressure is I have not checked this as of yet. Anyways I know fuel is being delivered to the injectors. Now I have had a plethora of codes comes and go over the last year since I bought her. I'm having an oxygen/emissions code come and go frequently. My ABS /TRAC OFF SERVICE ENGINE LIGHT (located above tachometer)ARE ALWAYS ON TOGETHER. THEy COME ON TOGETHER AND DISAPPEAR TOGETHeR. I've had the right hand side service engine light come and go frequently, more so here lately. After my car would not start up it was throwing a code for TPS and CPS. I replaced the TPS. SHE STILL WONT START. I TOOK ALL SPARK PLUGS OUT INSPECTED FOR BROKEN OR CRACKED, THEN CLEANED THE CONTACTS WITH A PRECISION FILE AND SPACED HER PLUGS TO .060 AS SHE HAD ERRATIC SPACED PLUGS FROM TO .065- .072. THEY PROBABLY NEED REPLACING BUT JUST TRYING TO GET HER STARTED RIGHT NOW. I PULLED OUT THE PLEASE HELP NUMBER 1 PLUG AND CRANKED HER OVER, SHES SHOWING SPARK. I SPRAYED STARTING FLUID IN HER INTAKE MANI. . SHE SPUTTERED A LITTLE NOT MUCH AND SHE DIED QUICKLY... FIRST TIME I DID THAT SHE (BACKFIRED BACK THROUGH THROUGH THE INTAKE MANIFOLD IN CASE THAT WILL HELP ANY. ) SHE NOT SHOWING ANY SIGNS OF LIFE... I NEED MY GIRL BACK.
If it's easier to ask questions you can text or call my number 8088246877
Sounds like the car has quite a few issues to sort out. So, if it is reading that there is a bad Crankshaft Positioning sensor the spark may be off and not firing correctly. Believe this ties in with the DIS control module. Some TPS units need a multimeter to set correctly as it needs to be bolted in at the correct angle to read right for the computer. The CPS is located by the harmonic balancer and may need cleaned or the wires inspected for shorts or broken wires. An engine needs 3 basic things to run, fuel, spark and compression. Hope this helps.
VT247
2007 Equinox over heating, changed water pump as well as thermostat. there is no leakage that I see.
+frank foster Do a pressure leak down test of the cooling system. Usually this means hooking a pump up pressure cap to the radiator and seeing if the pressure drops. This will also give you an idea where the problem is, coolant will come out and / or make a 'hissing' noise.
VT247
Mine is leaking from there too! thought it was the thermostat but no. Thanks
Bubbles too from the container lol
Mine is at 223,000miles got it at 173k and not major problems but breaks and battery
So a coolant system pressure test to see exactly where the leak is. Hope this helps!
VT247
2004 Pontiac Aztek 3.4. Temp gauge fluctuates while driving and stopped at light. Dipstick and oil fill cap look clean(not milky)
Probably a bad head gasket. Do a pressure test of the coolant system.
VT247
H
My 2002 Oldsmobile Alero has the 3400, My cooling fans do not come on when engine is hot nor when I turn on the A/C. When I unplug the temp sensor the fans with come on immediately and stay on. I still replaced the temp sensor but that did nothing.
How high does the temp get? Mine usually has to be over the 3/4 mark for the temp. My advice would be to hook the car up to a good OBDII scanner and see if you can turn on the fans. Might be that it's not getting a reference signal to turn on the relays that control the fans.
VT247
Joshua Lange 2002 Venture here. That is a common problem as well. The fans i come on really hot or not at all.
What triggers the reference signal to the fans? Is it the coolant temp sensor or the PCM? Jw
2000 olds sillette replaced cracked heater hose in the back of the engine. Now over heats. Do I need to bleed the system? Thermostat? Help please
acceleration issues with my 2004 Buick Rendezvous. I replaced the fuel pressure sensor, give it a tuneup, changed fuel filter, cleaned
mass air flow sensor, Intake air control Value, and Erg value
repaired electrical connectors hub going to fuel pump, checked catalytic converter,
checked for vacuum leaks. I press on the gas no power, I go up hill
and it loses speed. it builds up speed slow. I will not get on the highway during rush that's a no no. Went to the dealer after no other shop could figure it out. 500 dollars worth of diagnostic testing same problem. I feel like i was ripped off by GM I was told to do this and that same problem. I replaced a fuse it solved a problem, I cleaned the mass air flow sensor, Intake air control Value, and Erg value it solved a problem. I got the same issue but i will pay for anymore diagnostic testing a waste of money. No more check engine lights but same problem. Help Please
Just a few thoughts. Could be the O2 sensor or possibly weak spark (plugs, wires, coil, coil pack module) It needs a lot of spark to jump the large gap of .060 for the spark plugs.
VT247
My fans won't come on. Temp gauge works and shows up past center, but fans won't come on. I can remove the top of the relay and push them down and force the fans on high. So motor/fuse/wire is ok. what controls the fans relay? great vid
Does the fan come on when you turn on your A/C? The fans won't come on until the temp gauge is way up. I can let my Aztek (3400 engine) idle for what seems like forever and the fans don't come on. This is because the engine isn't overheating. Does yours overheat with coolant coming out the reservoir? If so, then it may be that the fans aren't operating correctly. Try unplugging the coolant temperature sensor, it can be difficult to reach as it's a tight squeeze. This should turn on the fans as well as it is a default for the computer. But, to answer your question, the coolant temperature sensor reads the temp as being high, sends a signal to the computer (ECM, electronic control module), the ECM sends a reference signal for the relay to activate, the relay then sends the fan 12 volts to run and turn on. Hope this helps. : )
VT247
Right, I used to run the a/c to keep the fans on. The a/c doesn't work now, so the fans won't come on ever now. I bypassed the relay and run a switch to run them manually. Guess I need to see the ecm signal to the relay to prove ecm good. Thanks for responding!
Try unplugging the coolant temperature sensor and turn the car on. If the fans come on, they're working fine. If not, there's a problem. The coolant temp sensor is located by / under where the throttle cable hooks to and by the upper radiator hose.
VT247
UCRASH TOO
Ive got the evap issue should i start with the evap solenoid over the gas tank or the part by the throttle body the o2 sensors are reading bad also figured that was because of the evap letting out bad emissions too much unburnt fuel the 3.1 liter 2002 buick century has 85,000 miles on it
Check inside the upper intake where the EGR bolts on. They are prone to carbon up real bad there through the passages. Another evap issue I once had was the check engine light would come on due to a bad FTPS (fuel tank pressure sensor. It's located on top of the tank, but can be reached under the vehicle.
VT247
if your watching this, I'm sorry. Stay clear of the gm 3400. prone to intake gasket failure that tends to cause the main bearings to fail. they blow head gaskets easily when they get a little warm. and the cam shaft is known to give out. my Rendezvous has scrapped two of them. my neighbors Century blew up and my brother in-law's Alero has 60k miles and sounds like a sewing machine. look for something with the 3800. much better engine. plus it gets the same gas mileage and makes more power.
Thank you for your videos. They are so helpful! I was wondering if you could identify something for me. I found a small metal tube sticking out of the back of the intake plenum on passenger side. It's right in front of the alternator on my 2002 Venture. It seemed to just have rubber cap over it which had a hole torn in it so I replaced it with another rubber cap. I was wondering if you knew what this tube is and what purpose it serves.
+servant2myking It's a vacuum port. Some models may have used them and others not. Replacing the rubber cap was the right thing to do.
VT247
hey guy. 2000 alero. 3400. changed wires and plugs. car doesnt idle correctly still will not start also unless gas pedal is to the floor
check fuel pressure, might be the filter or pressure regulator
I have a 2000 chevy venture van 3.4L and the idle has been getting steadily rougher for the past couple of months. I changed the sparks recently to fix a separate issue but I still have a dead spot when I first start the engine that lasts only 1 second before the engine kicks in again and idles. Anytime I am idling the engine is running rough and the temperature increases to 1/2 way and up to 3/4 now as well. Temp will decrease at normal speed limits. After watching your video and another one that specifically focused on my make and model, I am leaning towards thinking that this could be either an exhaust vacuum leak, a misfire or an intake manifold gasket issue. What would you recommend I do now? Thanks for your time!
what was it?
Hello. Basic cost to do the head gaskets and intake manifold gasket job ??? To help with overheating
Depends on the shop. It's certainly not an easy job!
VT247
Is the motor you just went over an Impala or something different. I couldn't get a good look at it. But it look like an SUV...
This motor was in an Aztek. But they put the same engine in the Impala for many years. Often GM puts the same motor in several different vehicles.
VT247
@@Vacationtime247 Thank you so much for replying. Sorry it has taken me so long to get back to you. The inevitable happened yesterday as a Matter of fact. It was running really hot when I picked my son up from school yesterday.. and didn't make it a quarter mile until it had gotten so hot that it shut down on me as I was driving. Thank goodness I was able to get the car pulled off on the side of the road. I have been so frustrated with it that I haven't even bothered to go back to it and try to see if it will back. I would say I that I probably messed it for good. But again, Thank you so much for ur help.
@@brandiehoward8943 Aw that stinks. Not fun when a car completely self destructs. Hope you find a reliable replacement : )
VT247
Hi I have 2003 Chevy venture don’t know what going on but when I drive I have good heat and the temperature normal but when I park or wait for the red light the temperature gate go up hot and no heat. I put new radiator new water pump new cooling sensor new thermostat and still does the same thing I wonder it have to do with the head gasket please let me know thank you
Vacation time, my 3.4 l8tr 2004 grand am overheats but the gauge doesn't reflect that. I believe the gauge works cause it move between 190-215 degrees. But steam is coming out from under my hood sometimes. What do you think?
Get a lot of these type of questions about this engine, so here's where I'd start if it were mine. Do a coolant system pressure test after filling up the overflow with water. Once pressurized, listen and watch for water to come out. Bet that a gasket is blown and it's leaking somewhere. Replaced the head, intake and timing cover gasket on nearly every GM 3400 I've had.
VT247
i have a 2005 buick rendezvous 3.4 it seems to over heat after about 30 to 45 min. ive changed the temp. sensor thermostats. an the fans not to sure if my fans kick in properly when i turn ac on they seem to kick in with more speed oil is good no smoke comes out from the exhaust
Do a coolant pressure test to check for leaks and holds @12-15 psi
VT247
Ok so I am having trouble finding the bleed plug for coolant on the drivers side. All the videos i have watched show a plug on the passenger and driver side but those werent aleros same engine though. Is there really a second bleed plug on the driver side of the engine ? And just to clarify. The 2 cooling fans , do they both come on at the same time with 2 speeds or no. Because im going out to junk yard to get new fans. My mechanic couod actually feel that the motor wasnt moving right.
Believe my fans are either on or off not variable speeds and come on at the same time together. Could check yours by unplugging the temp sensor. It would set a code off, but would turn the fans on. The code would reset after a few starts. The bleeder screws are pointed out at 2:45 If you're having to continuously bleed air out of the system there's a problem. Doing a coolant system pressure test is a good way to find any leaks.
VT247
I just purchased a 02 rendezvous and the only motors that is suppose to come in it is the 3400 but the intake cover says 3100 how can you tell the difference and are they interchangeable with transmission and everything
Hey i have a question about over heating it doesnt over heat completly goes about 3 fourths of the way then goes back down once fans kick on but i believe i have a slow leak where the bleeder is mext to the water pump l.. What type of sealer should i use on that o ring
If you're referring to the metal tube that has the bleeder on, it has an o ring. I took mine off, cleaned it and also added some black silicone around it. Didn't leak anymore after. But, might do a coolant pressure test to find any other leaks and see if it holds pressure after.
VT247
If head gasket is leaking wouldn't water be getting into oil system?
Not necessarily. Coolant can also get into the combustion chamber or blow out the side of the engine into the atmosphere. If the engine coolant system isn't under any pressure and circulating correctly, it can and will overheat.
VT247
@@Vacationtime247 my 2003 Buick Century is running hot I change the water pump about 6 months ago no leaks I had to change a hose is it good but it just started out the blue overheating and then I tried to bleed the air system and then I did the thermostat so do I have to follow this video
@Vacationtime247 I do not have enough heat, 2000 Montana Van, runs not more than 1/4 on the gauge scale, the heat is not HOT, just luke warm. Thoughts? otherwise it runs good
Fill up the coolant to the appropriate level. Run the vehicle until warmed up. Bleed out the bleeder screws until all the air is gone. If the problem persists, do a coolant leak down test. This will expose any leaks that may or may not be visible. It should hold pressure and not drop quickly.
VT247
Have 2003 grand am gt 3.4, started missing, sounded like a knock but was firing it seemed inside intake behind Throttle body. Code is mb ass air flow and #3 misfire. Put on new cool, spark plug, still missing.
Any info on the 2003 Pontiac 3.4 misfire please respond, rutnbuck8@gmail
Might be a stripped out rocker arm bolt. On some 3400 the threads are not very strong and a small bolt that goes into the aluminum head. Would explain the knock and would also explain the misfire. Take a piece of rubber tubing, put one end where the sound is coming from. The other end to your ear and listen near the valve cover. You can drill and helicoil the stripped out bolt for a fix. Hope this helps.
VT247
We have over heating, a PO300 code, and hot water and bubbles in the overflow tank.
Uh oh! Certainly sounds like a bad head gasket to me. Could do a coolant system pressure test and check to see if it holds 12-15 psi.
VT247
Found "mayonnaise" in the oil cap. Yuck.
Yeah, blown intake or head gasket
I have one question and I just need to hear your thoughts on my 3400 impala
what is your e mail
What seems to be the problem?
VT247
Ours is overheating after new water pump and radiator, hoses, and it's hissing near the air filter hose; the end connected to the engine, and in the vicinity of the thermostat.... Wondering if and or what hose(s) it could be. 2002 Impala.
Probably not a hose but a gasket.
My heat gets hold then cold again..I have no white residue on my oil cap though.do you still think that would be the head gasket
I have the same issue. Can someone answer please?
@@kimberlyduran6934 my problem was the radiator cap lol
@That's Bank I don't have a radiator cap
Why are the coolant fans not running on my 2000 Olds Sillouette Van 3.4 L ? Fuse 1 is good.
good morning Bud. I have an 04 olds silhouette with a 3400 motor and I'm reading 2 codes. 300 & 171 codes. I did an in house oil change and plug/wire change and oil pressure dropped. I have to little flared tip things at opposite corners of the upper intake manifold and they're sulking in air. are these supposed to be capped off or lead into some other intake hose? also, bank 1 code (171) is that an upstream o2 sensor? I changed out the oil pressure sensor already too. my car is riding ROUGH and as soon as I turn on the a/c I lose power. please help.
Sorry for the late response. Been in Alaska working as a mobile mechanic. Back on the Cali coast again. Sounds a lot like a vacuum leak. I shoved a piece of sponge in between the bracket and vacuum tube. There should be no vacuum leaks. A misting spray bottle of water can help find vacuum leaks. Spray and monitor for idle change.
VT247
I have a 2003 chevy impala with the 3400. The other day the low oil pressure light kept dinging. Well i ignored it cause it's been doing that since I had the oil changed last month. So as i was driving the car became a little warm, not hot enough for me to stop tho and i was almost home so I kept going and then all of a sudden a mile from my house it acted as if it didn't want to go. I put my foot on the gas and had it pushed down to the floor and the spedometer just kept going down, then the cars temp went way up in no time and the check engine light started to flash. Thankfully I was almost home, so i pulled over and shut the car off. I popped the hood as a red light popped up that said hot coolant temp. Well i let it cool and walked home. When I came back that evening after a couple hours, I added coolant and water, went to start the car and it just cranked but didn't start. So after sitting and waiting it still woi ldnt start and now its like my battery has completely drained. Even after leaving it on the battery charger, I take it off and it's like it was never on there. I try to start it once or twice and all the lights go dead again. Even after 2 days of me trying to start it, still no start. And no leaks. The radiator is full the overflow tank is where it needs to be, and no leaks coming from anywhere. Now it has all that in it and hasn't been able to get it started to run so I can bleed the valves. Please help. ..
Check to see if you have spark and fuel. My bet is that it doesn't have one or the other and without both, the car won't start or run.
VT247
@@Vacationtime247 yeah i figured it out there was coolant in the water
HEY QUICK QUESTION , what about when the fans dont turn on to cool down the car
Unplug the coolant temperature sensor and see if they come on. If they don't, check the fuse and relay next.
VT247
Do you have access to a scan tool that reads live data? the fans will not engage until coolant temp gets to around 225F or so.
I have a 2001 chev impala 3400 it was cooling great wife drove home from work it sat overnight started fine in the morning was blowing good heat then it started blowing ice cold the hose from the pump is warm the hose to the t stat is cold both have no pressure however if you remove rad cap the coolant will over flow. oil is clean no leaks seen anywhere
+Kylee Sauter First, fill up the radiator and replace the cap, run the car for a short time to warm it up. Turn out the bleeder screws, one on top of the black tube coming out the top of the water pump the other by the thermostat, their 7mm. Wait until fluid comes out to let the air escape. This should give you pressure. If you have heat inside the car for a short time, then it goes away, retry the same process. If this keeps happening, the head gaskets may be blown. The GM 3400 is notorious for this problem.
To find out if the system will hold pressure do this test:
Fill up the radiator and do a coolant system pressure test. Autozone does the loan a tool program where you buy the tool, use it then return it for a full refund after you're done. Hook it up to where the radiator cap is and pump up the tester. The system should hold @ at least 15 PSI with no pressure drop. If you're unsure on how to do this, most any car repair shop can run this test for fairly cheap. Let me know if you have any further questions and how it turns out.
VT247
Ok another thing is I drove it today was blowing cold air temp was around 200-210 shut it off let it sit for about 10-15 mins then drove home an it had heat again then quit again
Try bleeding the system as I mentioned before. May just be low on antifreeze. Or it could be the head gasket. Hopefully it's the easier of the two.
VT247
I did the water pump and tried bleeding out the from the valves and no luck it overheats but not always just sometimes
Do a coolant system pressure test. My guess is that there is a leak somewhere. Check the oil, make sure it doesn't look like a milkshake inside. These motors had bad gaskets all around, the intake, timing cover and head gaskets always eventually blow out on these engines.
VT247
thanks for great video - i have had this problem for a while now. rough idle, but ONLY when its warm, and as soon as i push the pedal juuuust a bit it runs fine . i have replaced tps and iac , cleaned throotle body, and replaced several vakum hoses , but it stiiiil has a rough idle . COULD it possible be a simple thing as a fuel filter ? i drove it emty for about 5 months ago , and....did it come after that hmmm . i just think that IF it was some fuel problem it shouldn´t run great, but correct me if i´m wrong , could it be a bad intake ? it has some time that noise in idle like a misfire ...like a bad sparkplug wire, but changed em for 6 month ago with plugs . i´m going crazy cause if it a bad intake it should not drive that god. it JUST a rough idle - what am i missing ? please ...please help me if you got a clue
Check fuel pressure, the port to check it is behind the power steering pump on the passenger side near the alternator. Could be a bad fuel pressure regulator, partially clogged fuel filter or a weak pump. Not sure if it's ever had the gaskets replaced, but these engines are horrible about blowing gaskets. If it ever gets hot or to cold, try a coolant pressure test to see if it holds pressure.
VT247
@@Vacationtime247 thanks a hole lot for that reply. I will check it later today, as soon as i got that egr valve on again 😡 pain in the but to get to . Noticed that the pipe going from rubber between air filter and throttle body in to the valve cover - dont remember its name BUT it was totally lose in valvecover, MAYBY its that but i dont think it is. Next step is the fuel way. Never ever had a car with so many problems all the time . Especially the fu....ng gearbox ! BUT when it drives im on top off the world. Some cars you just get a feeling for and it aint JUST A CAR you know.
i want to add a note also. flush out the dexcool antifreeze. had to replace a head on a 2004 grand am because the dexcool ate ito the head soo deep it was no good
Rinker262 I got a 3.4 in my Grand Am and it’s been alright so far no issues. I also don’t push the engine so hard either and do all the proper maintenance that’s key.
Have an 2003 Impala 3.4 liter over heating issue ofcourse changed out da thermostat but didnt resolve da problemTried bleeding out da cooling system cause on a youtube video one of da links said da system was pressurized..but as yu xplained in yur video on da 3400 engine there are 2bleeder valve one on gooseneck housing but da other as states on video never should be touched cause it will make yu have an all day headache..lol..but wat if yu never really can get water to come out of da bleedere valves..problem i am having now..so frustrated wit da Impala please help any suggestions are welcomed..thanks
Fill up the radiator and do a coolant pressure test. Could have a leak or a blown gasket. Leaks will be easy to see after being pressurized as water will come out in force. If it doesn't hold pressure and no leak is found the head gasket is probably blown.
VT247
I mixed the push rods up in the 3.1 v6 motor, the head closest the radiator from drive side to passenger side, what order do they go in?
Intake pushrods are shorter than the exhaust. You'll know which is which by looking at where the valve goes. If the valve can be seen with the intake manifold off, it's the intake. If you can't see the valve, it's for the exhaust.
VT247