Please correct me if I am wrong, but shouldn't the throttle be wide open when you run theses tests? I was always told that with the throttle closed, you get incorrect pressure readings...
Hi, the wet reading on one of the cylinders is lower than dry reading..what could be the inference..? I have done dry & wet compression test on my VW Polo 1.2 TDI..the reading is lower in the wet test than the dry test on cylinder number 3..? Dry: 1 - 26.7 (Bar) 2 - 26.5 3 - 27.8 Wet: 1 - 27.6 2 - 26.7 3 - 26.3
Hi Eric Need Help! I have a 2001 toyota celica with a zzt230 engine. The problem is that the engine is shaking, is not running smooth and I have a misfire on cylinder 3. I change spark plugs HGK laser iridum, new ignition coils, new injectors, new engine cover gasket,change the engine electrical harness from another car, clean the MAF sensor with special cleaner, new air filter (when I bought the car had no air filter), delete the error code, let the ECU remap and the same problem came(misfire on cylinder 3). Please tell me what else to check. Thanks allot
Good video.. What can I do.? I have a triton v8 5.4 when the engine is cold has a 150 psi compression. But when is normal temperature the cilinder #7 lost compression. Do you know why.? Thanks.
Hey Eric, love your vids, really helped me a lot. I have a vauxhall astra 1.7 cdti, 120,000 thou. When I crank her over, idle is fine, but occasionally it sounds like it's being starved of fuel, blip the pedal and it's fine. There's no milkshake, timing done at 80 thou. Was thinking maybe injector blocked or bad plugs. Any ideas?
Probaly a dumb question but how do you remember where those plugs go back after? Do you mark or number them? Also why does it say to disable the fuel injection system and the ignition system when conducting an engine compression test in the ASE exam materials. It seems that if you were to disable the ignition system you would not be able to crank the engine, I'm confused please help me gain some clarity if you would be kind enough to Thanks
1. The spark plugs can really be put into whatever cylinder you'd like. There's not a specific one that each needs to go into, it's universal. 2. You aren't trying to turn over the engine when doing a compression test. So you disable the fuel injection so that the cylinders don't get fuel put into them. Since you took out the plug the fuel would not burn and would negatively affect your test results and could possibly have negative affects on the engine. 3. Disabling the ignition system makes it so that the spark plugs will not fire. Since we aren't trying to actually start the engine and there's no fuel to ignite we don't want the spark plugs firing. Disabling the ignition system will not affect the starter mechanism and it will still attempt to start the engine like normal, spinning the crankshaft, and moving the cylinders.
Hey steve, Im not a pro tech, You definitely don't have compression in #2 cylinder, I would do a cylinder leakage test to isolate intake valve, exhaust valve, head gasket. Good luck sir..
I got a dry test of #1 145 psi ,and 0 on the others, I was thinking timingbelt. a buddy said it could be head gasket. it will not start. got fuel checked with pressure test and has spark. how can I tell if it head gasket or timing belt? I think it timing belt. just didn't want to pull the timing cover.
Certainly has to be a belt. So check. Try to pull the cover back slightly, so you can get a finger or screwdriver to push on the belt to see if has any tension on it. I'm sure it doesn't.
George Edwards ya it was belt bottom was kinked,took main pully bolt off and felt 5 or 7 smaller bolts was pickig up wrench to take them off and a buddy that owns body shopsaid that they don't come off just tap pu;;y, so I had 2 x 4 and hammer tapping crank pully and it came off . looked at pully and the crankshaft broke.so it in scrapyard now.bought a jeep cherkee.
@jdmsrv93 I take them all out, makes for more accurate readings in my opinion, that way the other cylinders are not trying to compress while your doing the test.
when I first watched this video almost 12yrs ago, Eric had a couple hundred subs and now he's at 1.6mil subs.. well deserved! Thanks for all you do Eric and the detailed information you provide in all your videos, I'm currently watching it as a refresher.
@Yobidefy Actually this test was done on a working engine and the readings on an engine of this kind of mileage is actually pretty typical in my experience.
I liked Eric's old original honest style in his vids I'd say it's why he's done so well. I remember one Christmas When I discovered Eric's vids I watched the entire back-log ,Now it's all about about product placement and cheap tools .this vid was made when he was a real working mech or had that feel of hand to mouth. How ever the fixing it forward vids are a step in the right direction
Good video i might ad that if you have a gauge that has a air hose hookup you can use it to pressurize the cylinder and check for coolant leaks like a cracked head or bad head gasket by looking for bubbles in the radiator by taking off the cap.
it's a good idea to precisely measure the equal amount of oil for each cylinder for a wet test. This way you won't have to worry about putting more or less oil and gettng wrong readings thus possibly making a really bad decision about the engine.
if you have low compression.... your pulling the engine so it doesnt matter... a wet compression test is to figure out if its rings or valves.. really doesnt matter how much atf you dump in the cylinders
@Catass2089 The spark plugs don't make the engine turn over the starter does and yes you would do this same thing on any engine it's just a matter of putting the gauge in to measure the compression.
Some people would say yes, their argument being that a cold engine has better compression because the elements inside are cold and not expanded. So they recommend warming up the engine to get the metals to expand before checking compression to get a more "true" reading. I've never done a compression test so I can't give my opinion, but the logic seems reasonable.
Vincent Gutierrez I did mine warm and they all came out at 14.5 - 15 bar, this is in a 1996 Audi, I'll have to do one cold some day and a 'wet' test to see the difference.
One thing that is also kinda important is you need your throttle at Full Open to get an accurate compression reading. This at least applies on my B Series Honda engine. 1) Engine should be warm for an accurate reading (I understand that the piston rings expand with heat?) 2) Full Open Throttle 3) It is also best is all spark plugs are removed before starting An additional note is that you can buy a remote starter switch to make the process way easier and allows you to watch the gauge closer.
Great job on the compression test lesson. Keeping it within common sense and not to technical. Thank you very much. Look forward to seeing more teaching videos. My subject vehicle is a 97 Nissan D21 Hardbody Pickup.
@vatan1923 No but some have glow plugs that you can remove and do the test in the same way, with others you might be able to remove the injectors to insert the tool to do the test with the correct adapters.
Hi ericthecarguy i ask you do i need hold wide open the throttle because i saw another video that this guy put the pliers to hold the throtle is neccesary??
@TeeWeeQcKsteel Compression testing is just a start, if you really want to know where the leak is a leak down is the way to go. I believe I referred to that in the video and I believe I've posted a link in the description to it. Thanks for the comment.
Well my Acura TL 2002 model compression test is at 210 dry (didn't do it wet or should I have?) from cylinder 1 to Cylinder 6 I'm surely happy about that . Thanks Eric
@chamblizi I would fix the oil leak first and check the oil pressure with an analog gauge to see what pressure you really have, if the engine has noise AND low oil pressure it may be time for a rebuild or replacement.
@chamblizi You might want to recheck those oil numbers from what I remember it was either 10W 30 or 10W40 that those things used but even so you might have an oil consumption problem. As for the hard starting it might have nothing to do with the compression but perhaps a carburetor issue. As for the leaking sensor I'm not sure but it could be the oil pressure sensor.
It's much better to remove them all when testing. It puts less stress on your starter since it is only compressing air in the cylinder with the tester and the engine cannot accidentally start up if it doesn't have any spark plugs in it.
When it comes to my vehicle I feel like I don't want to know if it has bad compression... It would pretty much mean its toast. I'll keep living in denial an adding lucus to the gas lol.
@@1111comment I fond out I had a bad injector. I used a method I learned here on youtube. You touch a screw driver to the injector while the engine is running. You can feel it clicking. One was opening (clicking) irregularly.
What do you check next if you have good compression, spark and fuel on all cylinders, but there is one cylinder that does not fire no matter what. No check engine light either,
Dont forget to have the throttle WIDE OPEN when performing a compression test to allow maximum air intake. If you have an electronic throttle, place key on engine off and block open the throttle pedal all the way to the floor before cranking. Also, perform a COLD engine compression test and a WARM compression test. Some engines misbehave only when cold or only when at operating temp. Dont bother with the wet compression test unless you have a large variation from specifications.
Hi Eric. First of all, I would like to thank you for sharing your videos on RUclips, I love them. I am writing to you to make an inquiry, I have a pathfinder 2001 with 160.000km which uses 20w-50 mineral oil and water as a coolant, the question is, is it advisable to change the oil for a liqui moly 10w-40 synthetic and water for refrigerant? Thank you very much for everything.
Thank you, Eric..... I have seen your videos before, however some of the first ones we're too long for me.... So I didn't subscribed, but now I have. Just wanted to say thank you.
Hey there Eric. Been watching Your videos from a long time back when You had 4.01K subscribers lol. Love Your videos man always super informative and simplified. I took compression tests on an import engine that I sourced, it’s a D16Z6. My main question in doubt is, could the wet tests go abnormally high because of Carbon buildup on the piston heads? My Dry tests were between 158-164 through out all cylinders. For 5 revolutions. But the wet tests were exceeding 200+. One was 201, the others were 230, 240+.
PLEASE HELP: 98 Dakota 3.9 V6 has misfires on 1,3,5. What I’ve done so far: new catalytic converter, new o2 sensors, new plugs wires and distributor cap, new TPS, new idle control valve, new MAP sensor, new injectors on 1,3,5 (only codes I’m getting P0301, 303, 305). I’m going to do a compression test next but wondering if anyone has any other ideas 💡
Hi Eric, I hope I get lucky this time with a response from you. I have a '95 maxima. I did a cyl. head job. The cam followers got shuffled, and I put them back randomly. I was getting 125psi on all cyl.'s. I disengaged the camshafts and cyl. 2 tested at 165 psi after several attempts( why did it take more attempts to get to 165psi than in your video?) , so I rearranged the cam followers now I'm getting 125-150psi.
i have 2010 Aveo engine type LXV the BOOK says that i need to remove crank sensor. The problem is you have remove starter to get to it. do you see way get around this? MEANING NOT DISCONNECT SENSOR THANK YOU
Hello Eric, I got a chevy 327 fresh rebuilt with 10:1 CR on the paper. I turn on the engine and at the idle it runs roughly and shake. I check everything, vacuum leak ecc ecc...I found that instead to have at least 150 PSI like I should in a 10:1 CR engine, I have 120PSI and 1 piston 110. Could be that the problem? The question is how that can be possible if is a fresh rebuild? Maybe the machine shop made a mistake? thank you
have an code on cylinder #5 ( misfire )... just replaced spider fuel injector and did compression test on cylinder #5 & 7 and got 125 reading on both.. cleared code, ran the engine and misfire on #5 code returned. i'm stumped on what to do next....? 1998 GMC sierra 5.0 305 vortex engine (301,100 miles) Seafoam the fuel? will that help clean the valves of carbon?
2002 Mercedes C32 question at first start up I get a p0303 mostly after secondary airpump turns off now that it's cold..warmer weather it's accompanied by p0300 but I think the p0303 is naturally causing the p0300 multiple cylinder misfire...I replaced all plugs and swapped 3 time the coil pack between 1-3 and 6 with spark wires also. I changed fuel filter incase regulator bad...when car acts up misfire I turn off then on and car fine and no codes reappear. Driving car I don't feel any power loss even at WOT...do you think it might be compression? cats on cylinder 3 side? maybe faulty fuel injector?
I have a misfire on one cylinder on a 4 cylinder engine. Compression readings are Cyl1=125psi Cyl2=150psi Cyl3=125psi Cyl4=125psi So could having higher compression on that cylinder be a cause for misfire on it? Anybody?
I checked the compression before watching this video and I didn't remove all the spark plugs, I just removed one at a time as I checked each cylinder and replaced each plug as I moved to the next cylinder. How inaccurate would my readings be sense I didn't remove all the sparkplugs first?. Ps I was getting around 120psi each cylinder.
I own 2003 Caddy Deville. 4.6 liter. Tested and told, No compression at cylinder 4 or 7. Drove car 100 miles yesterday, runs good, rough at idle, shuts down. Go 19 miles per gallon. What can it be. Thanks. Can you Email me, at. Detectiveaperez
Eric I love your videos and they've helped me so much. But my 98 integra won't start and there's no spark. The dizzy rotor is also not turning. Im wondering if my timing belt snapped. The crazy thing is I replaced the ALL the belts less than 10k ago. What do you sugest? Thanks ahead.
Eric "the car guy", low compression leak down test appears to be in exhaust valves, (suspect timing chain is off ( if We were to take the roller fowlers out, (makes the valves seat) then run a compression test, would this not tell us if its heads, or timing? 👍👍👍👍👍👍
350 Olds engine in my 78 Seville. Low compression on all cylinders (100-110 lb) Vacuum is 16 inches at idle 18 max at 1200 RPM. No miss at any speed. No slack in chain, can the chain be off a tooth or two?
Hey man Im getting half the compression I should be getting, but its very consistent across all 6 cylinders. What could be off? I checked with another gauge, same result
Real quick buddy , dry 100 wet 110 across . 5.9 dodge 225k miles is that too bad ? Trying to find cause of smoke on first acceleration. Just pulled plenum and intake for nothing. No visible failure in gasket
Lol im watching it now 2019 and he’s got 1.3M subscribers
1.4M
And me in 2020
1.8
@@lshooku well me mustve lost 400k
Right. Still helpful as hell though. 🤙
Wish u were local to me so you'll b my go to guy for all my service needs...I enjoy watching all your videos
Thanks dude. Your video helped me 11 years later.
Great video. I think it's worth noting that the engine should be warmed up before performing the test.
Great teachings. Thank you very much sir.
Great videos, love the detail on each one which is missing from a lot of similar mechanics!
Thanks :)
Hi just like to say thanks fore explaining step by step in witch has help me sort out my car good job to as it saved me time and money
Please correct me if I am wrong, but shouldn't the throttle be wide open when you run theses tests? I was always told that with the throttle closed, you get incorrect pressure readings...
Hi, the wet reading on one of the cylinders is lower than dry reading..what could be the inference..?
I have done dry & wet compression test on my VW Polo 1.2 TDI..the reading is lower in the wet test than the dry test on cylinder number 3..?
Dry:
1 - 26.7 (Bar)
2 - 26.5
3 - 27.8
Wet:
1 - 27.6
2 - 26.7
3 - 26.3
Great video bro very helpful
What if you have an awsome idle, great on flat roads but have a hard time driving up hills?
Hi Eric
Need Help!
I have a 2001 toyota celica with a zzt230 engine. The problem is that the engine is shaking, is not running smooth and I have a misfire on cylinder 3. I change spark plugs HGK laser iridum, new ignition coils, new injectors, new engine cover gasket,change the engine electrical harness from another car, clean the MAF sensor with special cleaner, new air filter (when I bought the car had no air filter), delete the error code, let the ECU remap and the same problem came(misfire on cylinder 3). Please tell me what else to check. Thanks allot
@Ericthecarguy Learned something new today, thank you.
Good video.. What can I do.? I have a triton v8 5.4 when the engine is cold has a 150 psi compression. But when is normal temperature the cilinder #7 lost compression. Do you know why.? Thanks.
Hey Eric, love your vids, really helped me a lot. I have a vauxhall astra 1.7 cdti, 120,000 thou. When I crank her over, idle is fine, but occasionally it sounds like it's being starved of fuel, blip the pedal and it's fine. There's no milkshake, timing done at 80 thou. Was thinking maybe injector blocked or bad plugs. Any ideas?
Check for vacuum leaks
hahahaha... cause an engine is really a glorified air compressor. The cadence was priceless
So you warm up the engine or you do it cold?
Can this be done in a Diesel engine?
Probaly a dumb question but how do you remember where those plugs go back after? Do you mark or number them? Also why does it say to disable the fuel injection system and the ignition system when conducting an engine compression test in the ASE exam materials. It seems that if you were to disable the ignition system you would not be able to crank the engine, I'm confused please help me gain some clarity if you would be kind enough to Thanks
1. The spark plugs can really be put into whatever cylinder you'd like. There's not a specific one that each needs to go into, it's universal.
2. You aren't trying to turn over the engine when doing a compression test. So you disable the fuel injection so that the cylinders don't get fuel put into them. Since you took out the plug the fuel would not burn and would negatively affect your test results and could possibly have negative affects on the engine.
3. Disabling the ignition system makes it so that the spark plugs will not fire. Since we aren't trying to actually start the engine and there's no fuel to ignite we don't want the spark plugs firing. Disabling the ignition system will not affect the starter mechanism and it will still attempt to start the engine like normal, spinning the crankshaft, and moving the cylinders.
Thanks Gooont I appreciate the response.
i have a ck lancer compression is 100 psi is ths good
Do u have to remove the pin thats in the tube b4 the test???im using the autozone tester
Hey steve, Im not a pro tech, You definitely don't have compression in #2 cylinder, I would do a cylinder leakage test to isolate intake valve, exhaust valve, head gasket. Good luck sir..
I got a dry test of #1 145 psi ,and 0 on the others, I was thinking timingbelt. a buddy said it could be head gasket. it will not start. got fuel checked with pressure test and has spark. how can I tell if it head gasket or timing belt? I think it timing belt. just didn't want to pull the timing cover.
ps. no water in oil or on cap. engine just died and would not start. it was low on oil and got a little hot. no oil leaking anywhere either
Certainly has to be a belt. So check. Try to pull the cover back slightly, so you can get a finger or screwdriver to push on the belt to see if has any tension on it. I'm sure it doesn't.
George Edwards ya it was belt bottom was kinked,took main pully bolt off and felt 5 or 7 smaller bolts was pickig up wrench to take them off and a buddy that owns body shopsaid that they don't come off just tap pu;;y, so I had 2 x 4 and hammer tapping crank pully and it came off . looked at pully and the crankshaft broke.so it in scrapyard now.bought a jeep cherkee.
How many cylinders do I write down if I have five? ;)
I love this
"Today I hit 500 subscribers."
Today he has 1.5 million!
lol 500 subscribers LOL. Watching this now and he has 778k.
839k
1,100,874 views
where
Mike Gillett 985k now lmao
1 mil niggas
500 subs. Now you have over one million
12,000,000 right about now!
500 subscribers then, 500,000 now. We all appreciate you Eric!
Edit: 1.5M now
joeman543 and now 614k daym
+ROB ANDRETTI 676,238 and growing strong ...
+Adil Zaman 689,163
+josh mcbride 706,914.....
+joeman543 721,052 now :D
@jdmsrv93 I take them all out, makes for more accurate readings in my opinion, that way the other cylinders are not trying to compress while your doing the test.
when I first watched this video almost 12yrs ago, Eric had a couple hundred subs and now he's at 1.6mil subs.. well deserved! Thanks for all you do Eric and the detailed information you provide in all your videos, I'm currently watching it as a refresher.
@miniwee3 Yes you need to be at WOT when doing the test.
dang 500 subscribers. Now you have over 650K.
+Glycerin 740k now
+BigDirtyBasterd 978k
+Mystickneon 759k now
+Peter Cas 782,976 now
23k subs in 1 months wow, thats arround 700 subs per day
~ 795 k :)
@Yobidefy Actually this test was done on a working engine and the readings on an engine of this kind of mileage is actually pretty typical in my experience.
I liked Eric's old original honest style in his vids I'd say it's why he's done so well. I remember one Christmas When I discovered Eric's vids I watched the entire back-log ,Now it's all about about product placement and cheap tools .this vid was made when he was a real working mech or had that feel of hand to mouth. How ever the fixing it forward vids are a step in the right direction
It's crazy how I come back to use these old videos when he had 500 subs great guy
lol 500 subs, now i see 1.2M
@meganerchia Good eye, it was ATF. I just had an abundance of it so I put it in my oil can. ATF is oil with some additives and dye added.
Should you use a specific ATF for the wet test?
lol 500 subs eh? Think you're a little past that now.
this was in his old shop, from when he began his channel :) just a fyi
Good video i might ad that if you have a gauge that has a air hose hookup you can use it to pressurize the cylinder and check for coolant leaks like a cracked head or bad head gasket by looking for bubbles in the radiator by taking off the cap.
Thank you for saying “why” to do things. Soooo helpful.
Engine compression test Perfectly described and totally understood! Thank you Eric, now can help me understand my freakin wife?
Just get a new one, not worth fixing it.
@Mypringles Yea often the basic mechanical function of the engine is overlooked when dealing with performance issues. Good luck.
it's a good idea to precisely measure the equal amount of oil for each cylinder for a wet test. This way you won't have to worry about putting more or less oil and gettng wrong readings thus possibly making a really bad decision about the engine.
if you have low compression.... your pulling the engine so it doesnt matter... a wet compression test is to figure out if its rings or valves.. really doesnt matter how much atf you dump in the cylinders
@@Turboboob regular oil or thick stuff for the wet test?
@@mtrott101 5w30/10w30/atf, doesn’t matter. I’ve used it all with the same result.
@@mtrott101 wouldn't you use tge same oil your car takes?
@vTeChRDC5 I don't know the exact spec for that engine off of the top of my head but that doesn't sound bad at all.
LOL 500, now you have 1.3 mil! Keep up the great work Eric. Keep en coming. I learn something new every time.
You are a brilliant teacher! Keep up the good work
@orville534 Thank you for that, glad you like them.
Lol 500 subscriber mark. You're almost at 500,000 now!!
I wish you could work on my Honda
He makes these videos so you can work on your own honda
@liljoker062000 Thanks very much for that comment I really appreciate it.
914,052 from 500 to almost a million, he made it.. lol
How many of the people watching this are subaru guys? -_-
Dan_Vallush I'm a 4g63 guy..lol
Dan_Vallush I'm an rx7 guy
Celica life
Dan_Vallush zoom zoom
Subaru +1
@Catass2089 The spark plugs don't make the engine turn over the starter does and yes you would do this same thing on any engine it's just a matter of putting the gauge in to measure the compression.
Shouldn't the engine be to operational temperature?
No mate.
bazthehandyman
Oh right, cool (excuse the pun), save on petrol. Cheers.
Some people would say yes, their argument being that a cold engine has better compression because the elements inside are cold and not expanded. So they recommend warming up the engine to get the metals to expand before checking compression to get a more "true" reading. I've never done a compression test so I can't give my opinion, but the logic seems reasonable.
Vincent Gutierrez I did mine warm and they all came out at 14.5 - 15 bar, this is in a 1996 Audi, I'll have to do one cold some day and a 'wet' test to see the difference.
That'd be great! I'm always down for some good science and crunching numbers to clear up car myths haha
One thing that is also kinda important is you need your throttle at Full Open to get an accurate compression reading. This at least applies on my B Series Honda engine.
1) Engine should be warm for an accurate reading (I understand that the piston rings expand with heat?)
2) Full Open Throttle
3) It is also best is all spark plugs are removed before starting
An additional note is that you can buy a remote starter switch to make the process way easier and allows you to watch the gauge closer.
Great job on the compression test lesson. Keeping it within common sense and not to technical. Thank you very much. Look forward to seeing more teaching videos. My subject vehicle is a 97 Nissan D21 Hardbody Pickup.
@vTeChRDC5 What you're really looking for with this test is a variance of more than 20% between cylinders.
@vatan1923 No but some have glow plugs that you can remove and do the test in the same way, with others you might be able to remove the injectors to insert the tool to do the test with the correct adapters.
Hi ericthecarguy i ask you do i need hold wide open the throttle because i saw another video
that this guy put the pliers to hold the throtle is neccesary??
@1972JasonRS It's not often knock sensors go bad, you might want to check the wiring or the electrical connections one or both could be damaged.
@TeeWeeQcKsteel Compression testing is just a start, if you really want to know where the leak is a leak down is the way to go. I believe I referred to that in the video and I believe I've posted a link in the description to it. Thanks for the comment.
1.79m viewers 2024 July 8th
Well my Acura TL 2002 model compression test is at 210 dry (didn't do it wet or should I have?) from cylinder 1 to Cylinder 6 I'm surely happy about that . Thanks Eric
hes got 1.4 Million subs. He ain't answering no questions. Hes a RICH BOY!
@chamblizi I would fix the oil leak first and check the oil pressure with an analog gauge to see what pressure you really have, if the engine has noise AND low oil pressure it may be time for a rebuild or replacement.
All the power-mech students in our school are using your videos to learn online, good job mate!
Actually my friend you’ve got something that money can’t buy you’ve got a very nice pleasant voice to listen to ! Jim .
Oh, boy 500 subs! Today is 1.3M. Greeting from 2019, 9 years later.
@spiritwolf391 Glad you liked it, thanks for the comment.
From 500 subscribers to 1.35million on 9/2019. Rock on ETCG 🤘
@chamblizi You might want to recheck those oil numbers from what I remember it was either 10W 30 or 10W40 that those things used but even so you might have an oil consumption problem. As for the hard starting it might have nothing to do with the compression but perhaps a carburetor issue. As for the leaking sensor I'm not sure but it could be the oil pressure sensor.
Hey. Can I do this test. Compression test. One cylinder at a time. Remove one plug at a time replace back in after test & so on?
It's much better to remove them all when testing. It puts less stress on your starter since it is only compressing air in the cylinder with the tester and the engine cannot accidentally start up if it doesn't have any spark plugs in it.
When it comes to my vehicle I feel like I don't want to know if it has bad compression... It would pretty much mean its toast. I'll keep living in denial an adding lucus to the gas lol.
same boat. already swapped out so much and still have a rough idle.
@@1111comment I fond out I had a bad injector. I used a method I learned here on youtube. You touch a screw driver to the injector while the engine is running. You can feel it clicking. One was opening (clicking) irregularly.
What do you check next if you have good compression, spark and fuel on all cylinders, but there is one cylinder that does not fire no matter what. No check engine light either,
Dont forget to have the throttle WIDE OPEN when performing a compression test to allow maximum air intake. If you have an electronic throttle, place key on engine off and block open the throttle pedal all the way to the floor before cranking. Also, perform a COLD engine compression test and a WARM compression test. Some engines misbehave only when cold or only when at operating temp. Dont bother with the wet compression test unless you have a large variation from specifications.
One of the best info videos I've ever seen. To the point, and showed the diagnostics on how to perform them. Thanks bud.
Hi Eric.
First of all, I would like to thank you for sharing your videos on RUclips, I love them.
I am writing to you to make an inquiry, I have a pathfinder 2001 with 160.000km which uses 20w-50 mineral oil and water as a coolant, the question is, is it advisable to change the oil for a liqui moly 10w-40 synthetic and water for refrigerant?
Thank you very much for everything.
Hi..Eric i just want to say your videos are a great help for a DIY man like me...thanks for all your help and the videos help me out alot..!!!!
very informative,i dont kno how some pple can thumbs down this vid maybe they are mechanic that work at the dealer or shops haters lol.
Can't fault this video, you seem to have covered everything. Just wish every mechanic was up to your standard. Many thanks.
Thank you, Eric..... I have seen your videos before, however some of the first ones we're too long for me.... So I didn't subscribed, but now I have. Just wanted to say thank you.
Hey there Eric. Been watching Your videos from a long time back when You had 4.01K subscribers lol. Love Your videos man always super informative and simplified. I took compression tests on an import engine that I sourced, it’s a D16Z6. My main question in doubt is, could the wet tests go abnormally high because of Carbon buildup on the piston heads? My Dry tests were between 158-164 through out all cylinders. For 5 revolutions. But the wet tests were exceeding 200+. One was 201, the others were 230, 240+.
PLEASE HELP: 98 Dakota 3.9 V6 has misfires on 1,3,5. What I’ve done so far: new catalytic converter, new o2 sensors, new plugs wires and distributor cap, new TPS, new idle control valve, new MAP sensor, new injectors on 1,3,5 (only codes I’m getting P0301, 303, 305). I’m going to do a compression test next but wondering if anyone has any other ideas 💡
Hi Eric, I hope I get lucky this time with a response from you.
I have a '95 maxima. I did a cyl. head job. The cam followers got shuffled, and I put them back randomly. I was getting 125psi on all cyl.'s. I disengaged the camshafts and cyl. 2 tested at 165 psi after several attempts( why did it take more attempts to get to 165psi than in your video?) , so I rearranged the cam followers now I'm getting 125-150psi.
i have 2010 Aveo engine type LXV the BOOK says that i need to remove crank sensor. The problem is you have remove starter to get to it. do you see way get around this? MEANING NOT DISCONNECT SENSOR
THANK YOU
Hello Eric, I got a chevy 327 fresh rebuilt with 10:1 CR on the paper. I turn on the engine and at the idle it runs roughly and shake. I check everything, vacuum leak ecc ecc...I found that instead to have at least 150 PSI like I should in a 10:1 CR engine, I have 120PSI and 1 piston 110. Could be that the problem? The question is how that can be possible if is a fresh rebuild? Maybe the machine shop made a mistake? thank you
Got a puzzling compression reading. MY PSI should read 170. Cylinder (1) is reading DRY 130 - WET 200, can't understand why it went up to 200? Cylinder (2) DRY 90 - WET 125. Cylinder (3) DRY 85 - WET 93. Cylinder (4) DRY 95 - WET 120. Anyone got any idea?
Eric the smart guy
Its funny to see soo many comments that are very similar.
lol 500 subs, you/he has the current amount of subs as I am watching
have an code on cylinder #5 ( misfire )... just replaced spider fuel injector and did compression test on cylinder #5 & 7 and got 125 reading on both.. cleared code, ran the engine and misfire on #5 code returned. i'm stumped on what to do next....?
1998 GMC sierra 5.0 305 vortex engine
(301,100 miles)
Seafoam the fuel? will that help clean the valves of carbon?
2002 Mercedes C32 question at first start up I get a p0303 mostly after secondary airpump turns off now that it's cold..warmer weather it's accompanied by p0300 but I think the p0303 is naturally causing the p0300 multiple cylinder misfire...I replaced all plugs and swapped 3 time the coil pack between 1-3 and 6 with spark wires also. I changed fuel filter incase regulator bad...when car acts up misfire I turn off then on and car fine and no codes reappear. Driving car I don't feel any power loss even at WOT...do you think it might be compression? cats on cylinder 3 side? maybe faulty fuel injector?
I have a misfire on one cylinder on a 4 cylinder engine.
Compression readings are
Cyl1=125psi
Cyl2=150psi
Cyl3=125psi
Cyl4=125psi
So could having higher compression on that cylinder be a cause for misfire on it? Anybody?
I checked the compression before watching this video and I didn't remove all the spark plugs, I just removed one at a time as I checked each cylinder and replaced each plug as I moved to the next cylinder. How inaccurate would my readings be sense I didn't remove all the sparkplugs first?. Ps I was getting around 120psi each cylinder.
I own 2003 Caddy Deville. 4.6 liter. Tested and told, No compression at cylinder 4 or 7. Drove car 100 miles yesterday, runs good, rough at idle, shuts down. Go 19 miles per gallon. What can it be. Thanks. Can you Email me, at. Detectiveaperez
Eric I love your videos and they've helped me so much. But my 98 integra won't start and there's no spark. The dizzy rotor is also not turning. Im wondering if my timing belt snapped. The crazy thing is I replaced the ALL the belts less than 10k ago. What do you sugest? Thanks ahead.
Eric "the car guy",
low compression
leak down test appears to be in exhaust valves,
(suspect timing chain is off (
if We were to take the roller fowlers out, (makes the valves seat)
then run a compression test, would this not tell us if its heads, or timing?
👍👍👍👍👍👍
350 Olds engine in my 78 Seville. Low compression on all cylinders (100-110 lb) Vacuum is 16 inches at idle 18 max at 1200 RPM. No miss at any speed. No slack in chain, can the chain be off a tooth or two?
Hey man
Im getting half the compression I should be getting, but its very consistent across all 6 cylinders. What could be off? I checked with another gauge, same result
Wowzers!! He said “500 subscribers” ........Take a quick look above to see how many he has now ! Don’t stop believing people !!🙏🏽
Real quick buddy , dry 100 wet 110 across . 5.9 dodge 225k miles is that too bad ? Trying to find cause of smoke on first acceleration. Just pulled plenum and intake for nothing. No visible failure in gasket
2.1 mil views, congrats!
Do I need to disable the Vcm on Honda v6 2015 pilot 100k miles? I’m getting p0302 on and off, spark plug fouled