Hi:Loved your video on 4 reasons. Right in line with my problem. I have a 6.2 GMC LS in my '37 Chevy sedan and put a new engine harness on it made for that engine. Once I had the engine hooked up without rad, trany lines, or gas line, I squirted some fuel in and turned the key, it fired right up. I did this 4 times to show my buddies and my wife. I was doing a jig I was so excited. So I went to work getting else hooked up and in place. I went to start it and no spark. It made no sense at all. Now, weeks later, I still can't figure it out. Your video has now shed some light on the problem. Unless you can tell me more how to get to the bottom of it, I'll try your method. Thanks for the help. Wish you lived in town lol.
Glad to help brother! If you wanna help the channel and others who may be having similar issues, be sure to share this video on your favorite LS swap forum or Facebook group! Remember, when it comes to RUclips, sharing is caring. 🤣👍🏻
Bought a brand new GM Connect and Cruise L96 package, took our time installing, double checked everything and it would not fire. Watched your video and did not have cranking power, got that lined out and fired up immediately. Thank You so much!!! 1959 Chevrolet Apache truck now with all the new technolgy.
Great channel and lots of good info. Thanks! I have a 1977 K5 Blazer body that I'm going to drop onto this 2002 Suburban 2500 4X4 chassis with the 8.1L DBW throttle and 4L80. I have the Suburban body off; the chassis has been shortened 2' and the new mounts are in place for the K5 Blazer body. I removed the OEM under-hood fuse/relay box and all of the unnecessary wiring. (Standard procedure on most any swap, right?) This is when my dilemma began. When I supply power to all of my 12V+ wires, (they're all currently connected together with ring terminals on each wire and a new 1/4-20 bolt and nut that is tight) my FP relay clicks rapidly (about 3-4 times a second) and the fuel pump stays on. The engine will crank but not fire. When I plant the K5 Blazer body onto this chassis, I will be installing my own fuse block with the necessary relays to supply power to the engine, the transmission, the transfer case and of course the PCM. I know that two orange wires to the PCM are supposed to be constant 12V+ battery, and all of the other pink wires are supposed to be 12V+ in run and start. I have tried separating the orange wires and connecting power to them first, then to all of the other pink wires. It did not change anything. When I disconnect the C1 16-pin connector from the TAC module and then supply power to all of my 12V+ wires, my FP relay will cycle on for 2 seconds and then off like it's supposed to. The engine will crank and run, but only momentarily. I assume that's because the TPS is not connected with the TAC module C1 16-pin disconnected. Prior to removing the under-hood fuse/relay box assembly, the engine ran fine, and I had throttle. This is my third LS swap, but my first swap with DBW throttle. I'm very comfortable with the wiring and hardware aspects of these swaps. My tuning capabilities are limited to static changes to the PCM's, VATS, EVAP, EGR, downstream o2 sensors...I can turn things on and off, which is all that I have done thus far with this PCM. It ran fine with throttle AFTER I did those changes and BEFORE I removed the under-hood fuse/relay box. There's something that I'm not seeing. One member on HPT suggested that I reinstall the fuse box. Well, it's not that simple. I have de-pinned all of the wires from the 4 connectors under the fuse/relay box. That just aint going to happen! I have seen a few different posts on various different forums (Including HPT) for this exact same scenario, so I know that this is not a unique problem. But no solutions have ever been posted on any of those other forums or threads. I have many hours into this problem, more than I care to admit. I have a headlight test light that I have used to check the integrity of all of my wires. I know from experience that ohm checking or probing with a small test light will not detect problems in wiring where there's corrosion or bad connections. I have used the headlight test light to check all of the TAC module 16-pin connector wires as well as the TAC module 10-pin connector wires which all go to the accelerator pedal sensor. I have checked all of my grounds this way too. I am at the point now where I'm throwing parts at it. I have replaced the APP. A replacement TAC module is on the way. If that doesn't work, I'll be trying another PCM. I hate to use another two credits to unlock it, but I'm just at a loss. I have some voltage measurements below if you're kind enough to read and decipher them. I had everything powered up while doing these tests, and I was back probing the pins. This first list is made at the PCM and also at the sensors to eliminate voltage drops. I also measured the grounds with my VOM negative lead on the positive battery terminal. They will be displayed as 12v- readings. I did all of the other measurements with the negative lead of my VOM on the engine, to confirm a good ground. My battery charger was connected during these measurements because the fuel pump relay is "fibrillating", and the fuel pump runs constantly as long as the TAC module C1 16-pin connector is plugged in. Again, in addition to checking the voltages below, I also checked the integrity of all of those circuits using the headlight test light. PCM power supplies and grounds: C1-19, C1-75 Switched 12V+ both were 12.8V+ C1-20, C1-57 constant 12V+ both were 12.8V+ C1-1, C1-40, C2-1, C2-40 PCM ground all were 12.8V- Engine sensors: C2-54 MAP 5V reference 5.2V+ C1-2 CKP 12V+ reference 11.7V+ C2-39 CMP 12V+ reference 11.7V+ C2-9 FP relay control 11.7V+ TAC module C1 measurements: C1-1 TP1 sensor signal 1.05V+ C1-2 TP1 5V reference 5.0V+ C1-3 TP1 low reference 12.6V- C1-4 CC set/coast 0V C1-5 CC res/acc 0V C1-6 CHMSL voltage 4.95V+ C1-7 12V supply 12.8V+ C1-8 TAC motor 2 13.1V+ C1-9 TP2 5V reference 5.0V+ C1-10 TP2 low reference 12.8V- C1-11 TP2 sensor signal 3.95V+ C1-12 serial Data 3.95V+ (fluctuating) C1-13 serial data 3.95V+ (fluctuating) C1-14 CC on/off SW 0V C1-15 Gound 12.8V- C1-16 TAC motor 1 13.1V+ TAC Module C2 measurements: C2-A APP 3 low reference 12.8V- C2-B APP 2 low reference 12.8V- C2-C APP 2 signal 5.0V+ C2-D APP 2 5V reference 5.0V+ C2-E APP 3 5V reference 5.0V+ C2-F APP 1 sensor signal 0V C2-G APP 1 5V reference 5.0V+ C2-H open C2-J App 1 low reference 12.8V- C2-K App 3 sensor signal 4.9V+ (not used) A couple of things that struck me as odd: 1) I also saw this on a couple of other posts. The voltage on both of the throttle body motor terminals is 13.1V+ when everything else is down around 12.8V+. 2) There is no voltage on APP 1 sensor signal, but there is 5.0V+ on APP 2 and 3 sensor signal. 3) TP1 sensor signal is only 1.05V+ and TP2 sensor signal is 3.95V+, the same as the two serial data wires. A couple of other odd things. The 12V+ supply to the CKP and CMP sensors is at battery voltage with the TAC module C1-16 pin connector disconnected. When I reconnect that connector, those two voltages drop a full volt. Also, I have a temporary DLC in place. I can communicate with the PCM on HPT as long as the TAC module C1-16 pin connector is removed. When reconnected, no com. I know that this is a lot of information, but I'm just hoping that you've seen this scenario before and can lead me in the right direction. I am a big fan of Brendan on lt1swap.com. His pin-out information is spot on. He also has all of the schematics for this 8.1L. I have sent an email to him about a week ago, nothing back yet. Thanks for your time! Jeff
Great video. I have an issue with fuel. No fuel getting to the rail. Checked pcm not sending power to fuel relay. Fuel pump not getting power. Any idea ? Have an aftermarket Chinese harness.
I would start by by checking the signal wire for the fuel pump relay and making sure they put it in the correct pin of the PCM connector. I’ve never used one of the China harnesses but I have heard of people having issues with some of them being pinned incorrectly. You can download a wiring diagram for free at LT1 swap.com but the China harnesses aren’t color coded to GM spec so you’ll also need a multimeter to double check that the signal wire going to the fuel pump relay is the same wire at the pcm connector.
Glad I ran across you. I just rebuilt my V8 vortec 6.0 in my 2003 Escalade Ext. Followed all torque specs put it together, primed the engine. Had good oil flow through all the pushrods. Closed it up installed all new sensors, new coils, new wires, new injectors. Hooked ut all up tried to start no start. No start. Got my OBD2 code reader had codes P0335 and P0336. Codes for crank shaft position sensor issues. Went and got the old crank sensor reinstalled it. Same problem. Called GM dealer ship about the Key got advice to use my fob to lock and unlock the doors. Did that. Tried to start. No start still but the codes went away. Mind you I did have spark I knkw because I had help checking fir it and the way I did it it shocked the hell out of me. And fuel pressure. That definitely isnt an issue because after trying to constantly start it and using starter fluid the fuel system became over pressurized and spurt fuel out from the regulator all over the place. I immediately removed the negative battery cable so it would stop. What happened there is it became over pressurized it forced the regulator out of place. Anyway after doing what the GM guy told me the P0335 and P0336 codes went away and for a few attempted starts ut stayed away. However now I get code P1626.... and the check engine light stays on but the security light isn't on. So now we still crank but no start. I also trued the sequence programing for vats but that's useless to me because the security light isn't on but maybe you know more and can help. However I still get that code P1626 crank and no start. Forgive me if I may have misunderstood something you said that may help but don't think I did and I don't want to sound redundant. But if you can help please do. Single mom trying to get my truck going again.... Thank you.
P1626 is a security code. It usually means that the body control module either isn’t communicating with the PCM or it isn’t seeing what it needs to see from the ignition switch and is telling the pcm not to fire the injectors. It’s possible that maybe you’ve dislodged a wire from a connector or have a loose ground somewhere that’s causing the problem. It’s also possible that your key needs to be reprogrammed to the BCM. There may be a hack to fix this but I don’t know it. The only two ways I know to get around this is to either take the vehicle to the dealership and let them reflash the BCM and reprogram you’re keys/fobs, or option b would be to find someone with HP Tuners and have them just disable your VATS completely. I usually deal with swap vehicles, not factory LS equipped vehicles with BCMs and I’m gonna be honest, if you have the VATS disables all together I’m not sure how all that will work out with the BCM since it’s a factory application. I’m sorry I can’t be of more help but like I said, I really don’t have much experience with this exact issue. 🤷🏼♂️
@@BadLuckGarage No worries. I appreciate your response.... On GM trucks from some time up to 2007 they had standard Keys but they did have the Vats system where whenever Vats was activated you have to do a relearn procedure for passkey ( no transponder ).... Just thought id share what I learned...lol. Feel like im going to GM school of hard knocks....
Wow… BLG… thanks bud! When I heard number #1 I thought…. Sounds crazy, but I’ll be dammed was exactly that. Ignition relays are overly complex on some vehicles. When you said switched 12v, I literally bought a push button switch…. SOB fired right up and then laughed at me.
Hey bud this is my first swap ls3 engine tr6060 transmission everything hooked up no start I was watching this video chech my power wire 21.5 voltage on start switch no start I have a black wire said start signal where I connect this wire to?
Very useful info. Especially the o2 making it run crap. Just incase this helps anyone. I’m in the process of fitting a ls1 and I spent a good few hours at the wkend trying to find a no spark and injector pulse issue. Finally I traced the wires from pcm and it turned out the cam and crank sensor plugs were the wrong way round. I was amazed that gm had made these two plugs the same. Surely I can’t be the only one this has happened to.
Most harnesses are laid out in such a way that its physically impossible for the cam sensor plug to reach the crank sensor location if everything else in plugged in BUT I've seen people try to install harnesses upside down, from the front, and do all kinds of other things so nothing really surprises me at this point.
Could of blown ecu possibly idk i re pinned the factory hsrness to clean it up and took the blue and red protectors off and put the blue protector on the red one and the red one on the blue and plugged it in and kept blowing my ecm fuee
Well all be #1 problem fixed here! Stumbled on this video on the crapper watching about vats. Reminds me of the hot wire for older coils but the opposite, run while cranking and die after letting off key.
@@loomieloom no. Turns out they sent me an bad harness. Sent it back & ordered one from another company & it fired right up. Been running every since. Just got done towing a car actually.
Hey man quick question i have 12v in all i jectors and coil oscks when cranking i have 12v and ground to my pcm and have no power to my crabk or cam sensors
Hey what's up bro I did everything that you said in your video and my car still won't start I got power at the coil pack power at the injectors why cranking the key over is just cranking not starting
Good video. I understand that the grounds for the harness go to the heads. Where should the ground from the battery go and what other grounds need to be add? Are they ran in series?
I always do battery to frame, battery to engine, battery to chassis, and engine to chassis. It’s a little overkill but I never have grounding issues that way.
L98 into a Landcruiser, the E38 ecm has vats deleted, but not the clutch pedal interface. Donor car had the clutch position switch. Not needing it on the cruiser Do I need to get it deleted . Injectors not firing , power to them but not working. Yes have constant power to ecm when cranking.Cheers
where do I get the 12volt ignition from? I think this is my problem. I don't have a HEI lead. I have installed a custom harness and there are no other wires in my vehicle yet.
I’ll be checking the first especially. Another question: I checked fuel pressure and gauge shows ~65 PSI. Does this make sense? Will it go down once the motor starts?
Sounds like you’re overrunning the regulator. I’ve done videos on this. Usually when people try to run too large of a pump with a C5 corvette filter/regulator setup. They’re only rated for 255LPH max. So if you’re running a larger pump than that it will overrun and cause excessively high fuel pressure. In the video to demonstrate I used a Walbro 450 pump with the vette filter/ regulator and it ran it all the way up to almost 75psi. Not good for the pump or the regulator.
@@BadLuckGarage - I’m running a Walbro GSL 392 external pump (255 LPH, I think). The motor, 5.3 Vortec, was built by a shop and has the stock regulator and fuel rail. I thought 58 PSI was more of what I should be expecting. Could the regulator be bad? Any way to adjust, or “unstick it” if possible?
5.3 swapped into a Mazda B2200 using the Edelbrock pro flo 4 harness and ecu for Gen III LS . We have power the the coils key on and cranking but not getting any spark out of the plug wires . Coils , plug wires , plugs , and both the crank and cam sensors are new . Any ideas ?
@@davegillis2189 our problem had to do with the edelbrock pro flo 4 ecu are you sure the vats are turned off ? I've heard more than one story of someone paying to have it done and it not marking. I've seen countless people come to the group on Facebook stating that the vehicle won't run or will spit and sputter and die . almost every time it's the vats in which they they think is already off but for some reason sometime they dont work . Also make sure you have the right side coils on the right side of the engine because it does matter
@@sheldonstewart70 I had vats delete. I took it to my buddy and installed in his truck and it started. Looks like I'm only not getting injector pulse. Spray a little starter fluid and it fires for a second. Ugh this thing is driving me bonkers
Good morning. I'm still a novice to LS Swapping. Engine won't start. I had my wife crank over the car while I tested the spark plugs and the injectors for voltage. All tested good. I have a 6.0L L96 Gen IV (Vortec) and a new ECM configured by a master Tuner friend to a 2009 Corvette ECM with VATS, flex fuel and VVT settings removed. I have this ECM setup because I"m using a Tremec T56 Magnum Six Speed. The engine started easily on half a crank about a month ago when I fired it up. Recently a Friend helped me with Dakota Digital Cruise control wiring, and now the engine won't start. I think I understand what you said about the 12 Volt ignition wiring test is verified with power to coils and injector when cranking. Now I'm at a loss. Thanks for all the information you share. Any thoughts/ideas where to look next?? Regards Matt Politzer.
@@BadLuckGarage Haha! Thx! I must have missed it. What minute mark? I know you alluded to it, but looking for the actually "how to" test the injectors and coils *voltage" using a multimeter...
@@davidlubin7389 just use a multimeter. Grab and injector connector, Positive on injector power wire, negative to ground. Same with main coil harness. While someone is holding the key to the crank position as explained in the video.
@@davidlubin7389 Something definitely not wired correctly. It sounds like you’re using the original coil wire to power the harness directly instead of using it to trigger a relay to power the harness. 7 volts is enough to trigger a relay, but definitely not enough to run the harness without one.
Hi I keep blowing a fuse that stops one side of engine, had mechanic check it, he couldnt find the problem, he put bigger fuse in and its working right now, what could fix this problem? Thank you
Have my bmw e60 ls swap.... was running with low fuel pressure issues.... got that fixed now at 58psi but now it will only crank and not start... any suggestions would be appreciated.... going to start going thru all wiring to see if any damage or loose connections
So how does the ignition switch works if I have that ignition wire connected to the battery directly shouldn’t it work? With out ignition switch or does it need a ignition switch to work ?
There is an entire playlist of these LS Swap Tips and tricks videos on this channel. I would love to do more of these as they require no work and very little editing, lol. But the trade off is I’m not getting any work done on the project vehicles either. 😒 But if you’ve got any ideas for LS tech tips that I haven’t already covered please let me know and I’ll see what I can do about making a video.👍🏻
I have a question, by the way your video was awesome. Here is my problem. Just put in a new wiring harness DBW in my LS swap 5.3 gen 1. The motor started DBW would not work. I am now at a point can’t get the motor to run and the relay going to the Coils is cycling off and on which is the reason the motor will not start. It was working but now not. I’ve checked all the grounds 5 times, voltage is correct, battery is at full charge, why would the relay be cycling and not staying on? That is my 1st question. The Second, why can’t I get my peddle to work? I know I have 12 volts to the correct wires, the throttle cycles on startup I have seen it move on start up and hear it when you turn the key on, but know communication with the peddle.
Great video! I have a 5.3l LM7 DBW swap with standalone harness into a 1990 350 TBI truck. Turns over, but no start. - Checked grounds on frame to block, back of heads, and at relay/fuse box. (Yes, should and will consolidate grounds). All grounds are good. - VATS confirmed to be deleted with ‘write entire’ on HPTuners. - Have 12 volts to all pink wires on injectors and coils when key on and during cranking. Coil voltage drops to 11 volts when cranking. (Used a battery jump box to ensure good cranking power) - Checked all 8 injectors with impulse light. All fire off. - Checked spark at spark plug boot connection. All spark. - 55psi fuel with key on, drops a few psi when cranking. Any help is much appreciated!
I had a LS Swap installed in a 1982 B-Body. Was running fine but I noticed erratic shifts in the transmission. Parked car and started it the next day and after idling for about 10 minutes it fell dead. Ever since, cranks over but no start. I have a fault code of p0122. Any help?
Yes. Replace or clean the TPS that your code PO122 is telling you is bad. You might also check the wiring going to the TPS and make sure there are no breaks or loose connections.
I have a 2008 Pontiac G8 GT....I'm going from the L76(LS2sort of) to a LS3.... The LS3 is a NEW FULLY EQUIPPED CRATE ENGINE.....Now my question is the L76 has a three prong Oil level sensor on the pan.... but the LS3 doesn't so do I need to swap the oil pans or can I just delete that sensor as I check my oil all the time because I'm a quarter mile racer
@@BadLuckGarage I swapped my L76 in my G8 GT for a LS3 motor.....Now my L76 motor had a sensor on the oil pan and the LS3 doesn't.....Do I have to swap oil pans or can I delete that sensor...... because my warranty is very tricky with certain things and I don't want to VOID it ....but naturally if I need it for my engine to function properly for my application... obviously they can't void my warranty... it's a Blueprint Engine part# PSLS376OCTF...... I looked up the G8 GXP LS3 MOTOR AND THAT LS3 HAS THE OIL SENSOR ON IT. WTHELL!!!!! If you can answer or help me with any of this I'll gladly appreciate it....Thanks
Do have any videos on 4l60e trans not shift from 2nd to 3rd ...my old trans did it I bought a brand new one and the new one is doing the exact same thing..
If the brand new one has the same problem then it’s either your shift settings in the tune or a wiring issue. Make sure your transmission harness is pinned correctly, you’ve got 12 bolts going to the shift solenoids, and your grounds are good.
I’m having a problem with my ls1 swap ! As soon as I connect my vacuum line to my brake booster engine dies on me or when I cover the vacuum like with my thumb it shuts down as well any suggestions
So i just wanted to also mention something else my exhaust pipe is exteneded 16 to 18 inchs roughly from my o2 sensor given that info is it still likely this could be my issue. Note the car does run just after it gets warm it runs like ish and then when i cut it off and back on it runs like crap right away almost.
Hey so i have a 2005 silverado that was a v6 and i put a 2002 engine in it. Im going to do a drive by cable should i use the 2005 harness or a 2003 and under harness?thanks
Hey what’s up bro how you doing my LS swap won’t start I got power at the coils on the keys turned on position I got power acting injectors where do I have to turn the key over to see if the coil packs and stuff are getting power or just on to the on position I want to 87 Camaro third GEN
Just a quick note finally figured it out it was another ground bottom front on cross member single black outside harness not the one that goes to lights must be 5-6 different grounds wow thanks
So I have a 71’ cj5 with a 5.3 and while it’s cranking its not getting spark 90% of the time because sometimes it will get spark and try to fire up but dies agin and just sits there and cranks, it used to start with no issue and for context it has been mudding and gotten wet and after that seems to be when the problem started
So it sounds to me like I’m having the number one issue you described. Did a Gen 4 swap on a 2010 chevy 1/2 ton. Did a full delete kit on dod/afm. Can’t find any ground issues or connection issues. No spark on no 1 or no 3 cylinders definitely had help to do that. The guy who did the ecm delete for the dod/afm read smog, throttle body, cam position, traction/ stable trac control codes and they wouldn’t clear. Cranks and cranks but no fire. I’m lost. Don’t know where to start. Cleaned some grounds and now only reads limited power on the dash but that’s in my shop without a reader. Still no spark.
I heard If your running it on a stand, you attach all the pink wires together and orange wires are constant hot, I did this and still isn't firing up, I got good grounds, I got spark on the plugs when turning over but won't fire up
Can you help me out I have the same problem but I'm trying to get a better understanding of it so I can see if I was close of understanding it better..
Okay on mine I still have the V6 batter cable goes to the alternator but it's short for the V8 I add a other batter cable with a fuse in-between and ran it to the battery fuse box bolt...
@Bad Luck Garage thanks. I assume the performance style intakes sacrifice low rpm power for all top... heard good things about a trailblazer ss one though.
Yes with the exception of the FAST intakes, most aftermarket intakes make more peak power at the expense of low end power. The NNBS/TBSS truck intake is the all around most powerful factory style catherdral port intake manifold.
Got a question.... my ls swap has been running fine and all of a sudden it started missing on high rpm decel and started draining the battery and then u went to start it and now it will not start. It will hit every once and while but will not start and run . Any ideas where I should look ?
Hey buddy I done a swap my car was running fine and driving fine till one day I started it and it ran and cut off. I have a Holley terminator that I changed the relay cause it was wet and it ran again and now it's doing it again and I changed the relay but still want run and we're getting plenty of fuel
Amazing Video!!! I have a slightly different situation that you might be able to help me with. I removed and reinstalled my LS3 engine into the same car, 2014 Camaro SS. Everything is hooked back up but we are not getting any crank. We put the key in and we get power but when we go to start it, everything shuts off. We benched the starter and it is good to go. We will look into "checking for power at the coils and fuel injectors while we are cranking but do you have any other troubleshooting ideas we can try?
Same as any car brother. I run grounds from battery to frame, body, and engine block. Then ground from engine to body. But those aren’t the grounds I’m referring to in the video. I’m referring to the engine harness grounds. There are usually two that goto the back of the heads and sometimes one at the front. It all depends on what harness you’re using.
I have a gen 4 5.3 that I pulled from a Yukon xl that I put in my 09 single cab Sierra and I haven’t been able to turn it over or even connect to the ecm. And the throttle body doesn’t open up. I ordered a brand new wiring harness hoping this fixes it and gives the engine power. Are you able to give me any word of advice when I get it re wired up?
Did a 76 Blazer 5.3 swap. Stock harness drive by wire. Runs for 3 seconds. has open stock manifolds. 02 sensors not hooked up yet. Is this why it stops? Thank you
It depends. 2007 was a crossover year for the Silverado. The “classics” still had the gen3 engine and pcm while the “New” trucks had the gen 4 pcm and engines. There are several visual differences. Most notably the intake manifold is different, the gen 4 has the knock sensors in the side of the engine instead of on top under the intake like the gen 3, and the gen 4 has a cam sensor in the front timing cover. Those are just a few quick ways to tell the difference.
I’m running rich got black smoke, the stock harness I got only has one female plug for 02s other is male won’t fit the sensor, not sure if that makes a big difference or not…
@@Guidi815 yup...pretty much(ebay harness).after installing an oil pressure gauge Inoticed I had "dead" acceleration pedal...it was working just fine before this.
@@mickbrowne2378 Google. But you don’t need a wire diagram to check all your connections and the pins in all the connectors and make sure everything has connectivity. Also make sure all grounds are tight as stated in the video. Not just connected....make sure they’re TIGHT. Check all fuses and relays. Make sure they’re operating properly. This all falls under “check your wiring and grounds”. 👍
Any update here?: I have an issue…crank, no start…LS1. I checked spark and have spark on ONLY cylinder #1! Any ideas? All plugs, wires, coils, and injectors are brand new. Thank you.
am doing an ls swap and i want to wire my starter relay as the factory truck donor ( 2002 chevy tahoe) Ppl wire from starter solenoid to pin 30 on relay, ground to pin 85 on relay, Yllw wire from NSS to pin 86 on relay, pin 87 not used and Ppl/Wht from NSS to fuse box but there no fuse to this wire and not connected to anything so my question is this factory relay wiring works to start the engine on or something is missing?
I have a 4th gen fbody that was v6 I swapped to ls and it’s only running one side of the motor I was wondering if you’ve came across this problem and how did you fix it
Is it normal for my 5.3 that is built putting out around 419 rear wheel horsepower..... is it normal for it to have a major sucking noise through the air filter on a 1026 Nick Williams throttle body and a 102 fast intake
Hi need help I did ls swap on my 71 Camaro and it had 4l80e now I swap to tr6060 now my car crank but not starting.do you think it could be pcm setting?
Hey I know this is a old video but maybe I can still find help, ls swap starts then dies instantly? I have the whole original setup just in a different frame any input on where to start?
Man that’s the nail on the head before I started tuning I was so dumb to how smart these pcms are or how much of a pain they are as well lol I would never think to put it in open loop I mean that’s how we tune fueling duh wouldn’t dawn on me with the fresh air so close to your o2s the STFT would freak out thank you brother GOD BLESS.
Yea we tend to overlook things sometime. If you go back and watch the exhaust video in the DR Nova playlist I was like “what the hell is going on!!??” I actually at one point mention that it could be because of the open headers but then I was like naw, it’s gotta be something else. Damn thing started running so crappy we were barely able to limp it off the trailer. They finished building the exhaust, I reset the LTFTs and BOOM it was running great. Sometimes second guessing myself all the time is a course. 🤦🏼♂️
Bad Luck Garage yeah I want to say it’s happen to me as well but I just below it off and finished assembling everything lol so I’m thinking that exactly what it was
I have an issue…crank, no start…LS1. I checked spark and have spark on ONLY cylinder #1! Any ideas? All plugs, wires, coils, and injectors are brand new. Thank you.
I am not even sure why you have so little subscribers. I find that insulting. The amount of knowledge and charisma you have speaks for itself.
This man is a national treasure! Thanks for the guidance. 5 minutes into this video and my problem is solved.
Glad to hear it brother! Be sure to share the video for others that may be having these issues!
Can you do a video on how to wire the 12v ignition to a switch inside the cab so I don’t have to do the gas work I’m trying to find a wire
Thanks!
1st one was my problem 😅, thanks for your information 👍🏼
Glad the video helped brother. And thank you for the super thanks, But you didn’t have to do that. My videos are free to help others.
Your first guess was exactly my problem. We now have an LS3 that runs and sounds awesome. Thank you VERY MUCH!
Glad to hear it helped brother!
For my LS2 Holden L76 swap it took the "Write Entire" to get past VATS. Thanks for the help, really made my day.
I have a l77 swap it’s cranking but not starting and I’m not getting coil packs do you know why ?
Hi:Loved your video on 4 reasons. Right in line with my problem. I have a 6.2 GMC LS in my '37 Chevy sedan and put a new engine harness on it made for that engine. Once I had the engine hooked up without rad, trany lines, or gas line, I squirted some fuel in and turned the key, it fired right up. I did this 4 times to show my buddies and my wife. I was doing a jig I was so excited. So I went to work getting else hooked up and in place. I went to start it and no spark. It made no sense at all. Now, weeks later, I still can't figure it out. Your video has now shed some light on the problem. Unless you can tell me more how to get to the bottom of it, I'll try your method. Thanks for the help. Wish you lived in town lol.
I followed your first step and it worked. I can't thank you enough you saved me big time keep up the great videos
Glad to help brother!
Can you explain this to me I think this might be my problem
First reason was my problem. Found the correct wire and bingo! Very much appreciate this video! Saved me a hell of a lot of time!
Glad to help brother! If you wanna help the channel and others who may be having similar issues, be sure to share this video on your favorite LS swap forum or Facebook group! Remember, when it comes to RUclips, sharing is caring. 🤣👍🏻
@@BadLuckGarage yessir, will do!
Thank you sir! Thats how we grow!
@@BadLuckGarage absolutely!
What wire is it?
Thank you so much for this, number one fixed my problem.
I was pulling my hair out over this. What a relief.
Glad the video helped brother. 👍
Bought a brand new GM Connect and Cruise L96 package, took our time installing, double checked everything and it would not fire. Watched your video and did not have cranking power, got that lined out and fired up immediately. Thank You so much!!! 1959 Chevrolet Apache truck now with all the new technolgy.
hi thank you for all this good info im having those problem with my motor not staying running imma try wat you said . thanks again
.
My issue was the ground, bolt was bottomed out so connection wasn’t great. I really appreciate your video.
This made my car run within seconds of finishing the video. THANK YOU!!!
Glad the video helped you out brother. Be sure to share so it can help others! 👍
mate your a legend worked as soon as you explained it happy aussie here today
Glad it helped
Hello everyone, Do I still need to delete VATS if I took the motor and pcm from a donor truck that was running ? To my Ls swap?.
Thank you I had the wrong power source much appreciated.
You are welcome!
Great channel and lots of good info. Thanks! I have a 1977 K5 Blazer body that I'm going to drop onto this 2002 Suburban 2500 4X4 chassis with the 8.1L DBW throttle and 4L80. I have the Suburban body off; the chassis has been shortened 2' and the new mounts are in place for the K5 Blazer body. I removed the OEM under-hood fuse/relay box and all of the unnecessary wiring. (Standard procedure on most any swap, right?) This is when my dilemma began. When I supply power to all of my 12V+ wires, (they're all currently connected together with ring terminals on each wire and a new 1/4-20 bolt and nut that is tight) my FP relay clicks rapidly (about 3-4 times a second) and the fuel pump stays on. The engine will crank but not fire. When I plant the K5 Blazer body onto this chassis, I will be installing my own fuse block with the necessary relays to supply power to the engine, the transmission, the transfer case and of course the PCM. I know that two orange wires to the PCM are supposed to be constant 12V+ battery, and all of the other pink wires are supposed to be 12V+ in run and start. I have tried separating the orange wires and connecting power to them first, then to all of the other pink wires. It did not change anything.
When I disconnect the C1 16-pin connector from the TAC module and then supply power to all of my 12V+ wires, my FP relay will cycle on for 2 seconds and then off like it's supposed to. The engine will crank and run, but only momentarily. I assume that's because the TPS is not connected with the TAC module C1 16-pin disconnected.
Prior to removing the under-hood fuse/relay box assembly, the engine ran fine, and I had throttle. This is my third LS swap, but my first swap with DBW throttle. I'm very comfortable with the wiring and hardware aspects of these swaps. My tuning capabilities are limited to static changes to the PCM's, VATS, EVAP, EGR, downstream o2 sensors...I can turn things on and off, which is all that I have done thus far with this PCM. It ran fine with throttle AFTER I did those changes and BEFORE I removed the under-hood fuse/relay box. There's something that I'm not seeing. One member on HPT suggested that I reinstall the fuse box. Well, it's not that simple. I have de-pinned all of the wires from the 4 connectors under the fuse/relay box. That just aint going to happen!
I have seen a few different posts on various different forums (Including HPT) for this exact same scenario, so I know that this is not a unique problem. But no solutions have ever been posted on any of those other forums or threads. I have many hours into this problem, more than I care to admit. I have a headlight test light that I have used to check the integrity of all of my wires. I know from experience that ohm checking or probing with a small test light will not detect problems in wiring where there's corrosion or bad connections. I have used the headlight test light to check all of the TAC module 16-pin connector wires as well as the TAC module 10-pin connector wires which all go to the accelerator pedal sensor. I have checked all of my grounds this way too. I am at the point now where I'm throwing parts at it. I have replaced the APP. A replacement TAC module is on the way. If that doesn't work, I'll be trying another PCM. I hate to use another two credits to unlock it, but I'm just at a loss.
I have some voltage measurements below if you're kind enough to read and decipher them. I had everything powered up while doing these tests, and I was back probing the pins. This first list is made at the PCM and also at the sensors to eliminate voltage drops. I also measured the grounds with my VOM negative lead on the positive battery terminal. They will be displayed as 12v- readings. I did all of the other measurements with the negative lead of my VOM on the engine, to confirm a good ground. My battery charger was connected during these measurements because the fuel pump relay is "fibrillating", and the fuel pump runs constantly as long as the TAC module C1 16-pin connector is plugged in. Again, in addition to checking the voltages below, I also checked the integrity of all of those circuits using the headlight test light.
PCM power supplies and grounds:
C1-19, C1-75 Switched 12V+ both were 12.8V+
C1-20, C1-57 constant 12V+ both were 12.8V+
C1-1, C1-40, C2-1, C2-40 PCM ground all were 12.8V-
Engine sensors:
C2-54 MAP 5V reference 5.2V+
C1-2 CKP 12V+ reference 11.7V+
C2-39 CMP 12V+ reference 11.7V+
C2-9 FP relay control 11.7V+
TAC module C1 measurements:
C1-1 TP1 sensor signal 1.05V+
C1-2 TP1 5V reference 5.0V+
C1-3 TP1 low reference 12.6V-
C1-4 CC set/coast 0V
C1-5 CC res/acc 0V
C1-6 CHMSL voltage 4.95V+
C1-7 12V supply 12.8V+
C1-8 TAC motor 2 13.1V+
C1-9 TP2 5V reference 5.0V+
C1-10 TP2 low reference 12.8V-
C1-11 TP2 sensor signal 3.95V+
C1-12 serial Data 3.95V+ (fluctuating)
C1-13 serial data 3.95V+ (fluctuating)
C1-14 CC on/off SW 0V
C1-15 Gound 12.8V-
C1-16 TAC motor 1 13.1V+
TAC Module C2 measurements:
C2-A APP 3 low reference 12.8V-
C2-B APP 2 low reference 12.8V-
C2-C APP 2 signal 5.0V+
C2-D APP 2 5V reference 5.0V+
C2-E APP 3 5V reference 5.0V+
C2-F APP 1 sensor signal 0V
C2-G APP 1 5V reference 5.0V+
C2-H open
C2-J App 1 low reference 12.8V-
C2-K App 3 sensor signal 4.9V+ (not used)
A couple of things that struck me as odd:
1) I also saw this on a couple of other posts. The voltage on both of the throttle body motor terminals is 13.1V+ when everything else is down around 12.8V+.
2) There is no voltage on APP 1 sensor signal, but there is 5.0V+ on APP 2 and 3 sensor signal.
3) TP1 sensor signal is only 1.05V+ and TP2 sensor signal is 3.95V+, the same as the two serial data wires.
A couple of other odd things. The 12V+ supply to the CKP and CMP sensors is at battery voltage with the TAC module C1-16 pin connector disconnected. When I reconnect that connector, those two voltages drop a full volt. Also, I have a temporary DLC in place. I can communicate with the PCM on HPT as long as the TAC module C1-16 pin connector is removed. When reconnected, no com.
I know that this is a lot of information, but I'm just hoping that you've seen this scenario before and can lead me in the right direction. I am a big fan of Brendan on lt1swap.com. His pin-out information is spot on. He also has all of the schematics for this 8.1L. I have sent an email to him about a week ago, nothing back yet. Thanks for your time! Jeff
This video is spot on thanks for putting this out there .
Glad it was helpful!
very good video you did here ,, good tips,,, its too bad not one helped me with what I got going
Great video. I have an issue with fuel. No fuel getting to the rail. Checked pcm not sending power to fuel relay. Fuel pump not getting power. Any idea ? Have an aftermarket Chinese harness.
I would start by by checking the signal wire for the fuel pump relay and making sure they put it in the correct pin of the PCM connector. I’ve never used one of the China harnesses but I have heard of people having issues with some of them being pinned incorrectly. You can download a wiring diagram for free at LT1 swap.com but the China harnesses aren’t color coded to GM spec so you’ll also need a multimeter to double check that the signal wire going to the fuel pump relay is the same wire at the pcm connector.
We actually did what u said about checking the number 1 coil n plug if I’m correct of the steal to see it fire 🔥
Thanks for the tips! I want to do a LS swap on my 78 Corvette I just haven't done it yet.
You can do it!
Great knowledge Robert! 👍 thank you bad luck garage
Glad I ran across you.
I just rebuilt my V8 vortec 6.0 in my 2003 Escalade Ext.
Followed all torque specs put it together, primed the engine. Had good oil flow through all the pushrods. Closed it up installed all new sensors, new coils, new wires, new injectors.
Hooked ut all up tried to start no start. No start.
Got my OBD2 code reader had codes P0335 and P0336. Codes for crank shaft position sensor issues.
Went and got the old crank sensor reinstalled it. Same problem.
Called GM dealer ship about the Key got advice to use my fob to lock and unlock the doors. Did that. Tried to start. No start still but the codes went away.
Mind you I did have spark I knkw because I had help checking fir it and the way I did it it shocked the hell out of me. And fuel pressure. That definitely isnt an issue because after trying to constantly start it and using starter fluid the fuel system became over pressurized and spurt fuel out from the regulator all over the place. I immediately removed the negative battery cable so it would stop. What happened there is it became over pressurized it forced the regulator out of place.
Anyway after doing what the GM guy told me the P0335 and P0336 codes went away and for a few attempted starts ut stayed away. However now I get code P1626.... and the check engine light stays on but the security light isn't on. So now we still crank but no start.
I also trued the sequence programing for vats but that's useless to me because the security light isn't on but maybe you know more and can help. However I still get that code P1626 crank and no start.
Forgive me if I may have misunderstood something you said that may help but don't think I did and I don't want to sound redundant. But if you can help please do. Single mom trying to get my truck going again.... Thank you.
P1626 is a security code. It usually means that the body control module either isn’t communicating with the PCM or it isn’t seeing what it needs to see from the ignition switch and is telling the pcm not to fire the injectors. It’s possible that maybe you’ve dislodged a wire from a connector or have a loose ground somewhere that’s causing the problem. It’s also possible that your key needs to be reprogrammed to the BCM. There may be a hack to fix this but I don’t know it. The only two ways I know to get around this is to either take the vehicle to the dealership and let them reflash the BCM and reprogram you’re keys/fobs, or option b would be to find someone with HP Tuners and have them just disable your VATS completely. I usually deal with swap vehicles, not factory LS equipped vehicles with BCMs and I’m gonna be honest, if you have the VATS disables all together I’m not sure how all that will work out with the BCM since it’s a factory application. I’m sorry I can’t be of more help but like I said, I really don’t have much experience with this exact issue. 🤷🏼♂️
@@BadLuckGarage No worries. I appreciate your response.... On GM trucks from some time up to 2007 they had standard Keys but they did have the Vats system where whenever Vats was activated you have to do a relearn procedure for passkey ( no transponder )....
Just thought id share what I learned...lol.
Feel like im going to GM school of hard knocks....
Count me in on the majority. No power to the coils while cranking. Fixed that and it fires right up. Thanks!
Glad the video helped! Be sure to share it if you think it can help someone else!
Thanks so much just fired up my 5.3 k5 blazer, now that my crank sensor is plugged in
Glad you got her running brother!
Unfortunately for me I've already gone through these still won't start...
Any remedy?
Wow… BLG… thanks bud! When I heard number #1 I thought…. Sounds crazy, but I’ll be dammed was exactly that. Ignition relays are overly complex on some vehicles. When you said switched 12v, I literally bought a push button switch…. SOB fired right up and then laughed at me.
Glad the video helped brother. Be sure I share if if you think it could help others. 👍
Hey bud this is my first swap ls3 engine tr6060 transmission everything hooked up no start I was watching this video chech my power wire 21.5 voltage on start switch no start I have a black wire said start signal where I connect this wire to?
thank you SR. # 1 was my problem , and thanks to my dog that helped me crank my truck wile a was checking for power.😜
Lol
Great video! I am on my way to the shop now to go check my ignition switched power source! Fingers crossed!!!
I’m hoping I can pick your brain soon. I used a purchased harness. I am not getting power to my coils at all. Was hoping to get some help with that.
Very useful info. Especially the o2 making it run crap. Just incase this helps anyone. I’m in the process of fitting a ls1 and I spent a good few hours at the wkend trying to find a no spark and injector pulse issue. Finally I traced the wires from pcm and it turned out the cam and crank sensor plugs were the wrong way round. I was amazed that gm had made these two plugs the same. Surely I can’t be the only one this has happened to.
Most harnesses are laid out in such a way that its physically impossible for the cam sensor plug to reach the crank sensor location if everything else in plugged in BUT I've seen people try to install harnesses upside down, from the front, and do all kinds of other things so nothing really surprises me at this point.
@@BadLuckGarage right totally impossible
Could of blown ecu possibly idk i re pinned the factory hsrness to clean it up and took the blue and red protectors off and put the blue protector on the red one and the red one on the blue and plugged it in and kept blowing my ecm fuee
thanks you saved my sanity, been checking shit for hours and 5 min of video i fixed problem
Love hearing that brother!! Please share this video on social media so it can help others as well!
@@BadLuckGarage shared on facebook
Thanks brother. Sharing helps others and it also helps the channel grow!👍
@@larrydavis2512 what did you do
Well all be #1 problem fixed here! Stumbled on this video on the crapper watching about vats. Reminds me of the hot wire for older coils but the opposite, run while cranking and die after letting off key.
Glad the video helped you out brother.
Just changed out motors and ignition Cylinders. Starter not engaging. Powers on but no engaging of ignition
Sounds like it’s time to grab a test light and forgive out where the power stops.
I haven’t hooked up my O2 sensors yet. Do you think that will stop my engine from starting at all? I checked everything else & it still want start.
Im having the same issue and I dont have my 02 sensors plugged up either did you get your running was it the unplugged sensors
@@loomieloom no. Turns out they sent me an bad harness. Sent it back & ordered one from another company & it fired right up. Been running every since. Just got done towing a car actually.
Hey man quick question i have 12v in all i jectors and coil oscks when cranking i have 12v and ground to my pcm and have no power to my crabk or cam sensors
Hey what's up bro I did everything that you said in your video and my car still won't start I got power at the coil pack power at the injectors why cranking the key over is just cranking not starting
Good video. I understand that the grounds for the harness go to the heads. Where should the ground from the battery go and what other grounds need to be add? Are they ran in series?
I always do battery to frame, battery to engine, battery to chassis, and engine to chassis. It’s a little overkill but I never have grounding issues that way.
@@BadLuckGarage Thanks for your insight. I’m going to try that.
@@christopherwilliams8514 no problem brother. Good luck on the swap!
L98 into a Landcruiser, the E38 ecm has vats deleted, but not the clutch pedal interface. Donor car had the clutch position switch. Not needing it on the cruiser Do I need to get it deleted . Injectors not firing , power to them but not working. Yes have constant power to ecm when cranking.Cheers
where do I get the 12volt ignition from? I think this is my problem. I don't have a HEI lead. I have installed a custom harness and there are no other wires in my vehicle yet.
I explained in the video how to test for a 12v ignition wire.
I’ll be checking the first especially. Another question: I checked fuel pressure and gauge shows ~65 PSI. Does this make sense? Will it go down once the motor starts?
Sounds like you’re overrunning the regulator. I’ve done videos on this. Usually when people try to run too large of a pump with a C5 corvette filter/regulator setup. They’re only rated for 255LPH max. So if you’re running a larger pump than that it will overrun and cause excessively high fuel pressure. In the video to demonstrate I used a Walbro 450 pump with the vette filter/ regulator and it ran it all the way up to almost 75psi. Not good for the pump or the regulator.
@@BadLuckGarage - I’m running a Walbro GSL 392 external pump (255 LPH, I think). The motor, 5.3 Vortec, was built by a shop and has the stock regulator and fuel rail. I thought 58 PSI was more of what I should be expecting. Could the regulator be bad? Any way to adjust, or “unstick it” if possible?
5.3 swapped into a Mazda B2200 using the Edelbrock pro flo 4 harness and ecu for Gen III LS . We have power the the coils key on and cranking but not getting any spark out of the plug wires . Coils , plug wires , plugs , and both the crank and cam sensors are new . Any ideas ?
Hey bud did you figure this out? I'm having this issue myself
@@davegillis2189 are you using the edelbrock pro flo 4 harness and ecu ?
@@sheldonstewart70 No re-did factory harness
@@davegillis2189 our problem had to do with the edelbrock pro flo 4 ecu are you sure the vats are turned off ? I've heard more than one story of someone paying to have it done and it not marking. I've seen countless people come to the group on Facebook stating that the vehicle won't run or will spit and sputter and die . almost every time it's the vats in which they they think is already off but for some reason sometime they dont work . Also make sure you have the right side coils on the right side of the engine because it does matter
@@sheldonstewart70 I had vats delete. I took it to my buddy and installed in his truck and it started. Looks like I'm only not getting injector pulse. Spray a little starter fluid and it fires for a second. Ugh this thing is driving me bonkers
Good morning. I'm still a novice to LS Swapping. Engine won't start. I had my wife crank over the car while I tested the spark plugs and the injectors for voltage. All tested good. I have a 6.0L L96 Gen IV (Vortec) and a new ECM configured by a master Tuner friend to a 2009 Corvette ECM with VATS, flex fuel and VVT settings removed. I have this ECM setup because I"m using a Tremec T56 Magnum Six Speed. The engine started easily on half a crank about a month ago when I fired it up. Recently a Friend helped me with Dakota Digital Cruise control wiring, and now the engine won't start. I think I understand what you said about the 12 Volt ignition wiring test is verified with power to coils and injector when cranking. Now I'm at a loss. Thanks for all the information you share. Any thoughts/ideas where to look next?? Regards Matt Politzer.
Great video...have video on best way to check the power to the injector wires and coil use multimeter while cranking?
Yes, this one.
@@BadLuckGarage Haha! Thx! I must have missed it. What minute mark? I know you alluded to it, but looking for the actually "how to" test the injectors and coils *voltage" using a multimeter...
@@davidlubin7389 just use a multimeter. Grab and injector connector, Positive on injector power wire, negative to ground. Same with main coil harness. While someone is holding the key to the crank position as explained in the video.
@@BadLuckGarage thanks. Did that yestserday...in acc mode was at 12v, in crank was at 7v!
@@davidlubin7389 Something definitely not wired correctly. It sounds like you’re using the original coil wire to power the harness directly instead of using it to trigger a relay to power the harness. 7 volts is enough to trigger a relay, but definitely not enough to run the harness without one.
I have a aaw power 13 plus harness in my car with a holley stealth. Not sure where to get my hot. Ignition wire?
Hi I keep blowing a fuse that stops one side of engine, had mechanic check it, he couldnt find the problem, he put bigger fuse in and its working right now, what could fix this problem? Thank you
Do you have an idea , whats blowing fuse, the engine just shuts down when driving, Thanks
Have my bmw e60 ls swap.... was running with low fuel pressure issues.... got that fixed now at 58psi but now it will only crank and not start... any suggestions would be appreciated.... going to start going thru all wiring to see if any damage or loose connections
So how does the ignition switch works if I have that ignition wire connected to the battery directly shouldn’t it work? With out ignition switch or does it need a ignition switch to work ?
Yes
Lol didn't have a problem just a subscriber but that's how all how to videos should be!!!!! Great information thanks
There is an entire playlist of these LS Swap Tips and tricks videos on this channel. I would love to do more of these as they require no work and very little editing, lol. But the trade off is I’m not getting any work done on the project vehicles either. 😒 But if you’ve got any ideas for LS tech tips that I haven’t already covered please let me know and I’ll see what I can do about making a video.👍🏻
I have a question, by the way your video was awesome. Here is my problem. Just put in a new wiring harness DBW in my LS swap 5.3 gen 1. The motor started DBW would not work. I am now at a point can’t get the motor to run and the relay going to the Coils is cycling off and on which is the reason the motor will not start. It was working but now not. I’ve checked all the grounds 5 times, voltage is correct, battery is at full charge, why would the relay be cycling and not staying on? That is my 1st question. The Second, why can’t I get my peddle to work? I know I have 12 volts to the correct wires, the throttle cycles on startup I have seen it move on start up and hear it when you turn the key on, but know communication with the peddle.
What are Ls swappers connecting their fuel pump relay wire to in older cars. Can’t find any wires that are hot in run and start in my 65 nova
Explained in the video
Great video!
I have a 5.3l LM7 DBW swap with standalone harness into a 1990 350 TBI truck.
Turns over, but no start.
- Checked grounds on frame to block, back of heads, and at relay/fuse box. (Yes, should and will consolidate grounds). All grounds are good.
- VATS confirmed to be deleted with ‘write entire’ on HPTuners.
- Have 12 volts to all pink wires on injectors and coils when key on and during cranking. Coil voltage drops to 11 volts when cranking. (Used a battery jump box to ensure good cranking power)
- Checked all 8 injectors with impulse light. All fire off.
- Checked spark at spark plug boot connection. All spark.
- 55psi fuel with key on, drops a few psi when cranking.
Any help is much appreciated!
I’m having the exact same problem, did you ever get a response?
Did you ever receive a response I’m in the same boat.
Ever figure out the issue and get it running? I have a very similar issue with a NA motor
My tbss been sitting because I did a ls3. Swap turns on than turns off Ima try all of em see if It can be one of them
Got an LS tech tip or trick you'd like to see a video on? Post it in the comments and I'll see what I can do!!!
I had a LS Swap installed in a 1982 B-Body. Was running fine but I noticed erratic shifts in the transmission. Parked car and started it the next day and after idling for about 10 minutes it fell dead. Ever since, cranks over but no start. I have a fault code of p0122. Any help?
Yes. Replace or clean the TPS that your code PO122 is telling you is bad. You might also check the wiring going to the TPS and make sure there are no breaks or loose connections.
I have a 2008 Pontiac G8 GT....I'm going from the L76(LS2sort of) to a LS3....
The LS3 is a NEW FULLY EQUIPPED CRATE ENGINE.....Now my question is the L76 has a three prong Oil level sensor on the pan.... but the LS3 doesn't
so do I need to swap the oil pans or can I just delete that sensor as I check my oil all the time because I'm a quarter mile racer
@@BadLuckGarage I swapped my L76 in my G8 GT for a LS3 motor.....Now my L76 motor had a sensor on the oil pan and the LS3 doesn't.....Do I have to swap oil pans or can I delete that sensor...... because my warranty is very tricky with certain things and I don't want to VOID it
....but naturally if I need it for my engine to function properly for my application... obviously they can't void my warranty... it's a Blueprint Engine part# PSLS376OCTF...... I looked up the G8 GXP LS3 MOTOR AND THAT LS3 HAS THE OIL SENSOR ON IT. WTHELL!!!!! If you can answer or help me with any of this I'll gladly appreciate it....Thanks
Got a lt1 ls motor and i believe the crank on position is the issue with no start.. Do you have a video of how to check the hot crank position on?
Do have any videos on 4l60e trans not shift from 2nd to 3rd ...my old trans did it I bought a brand new one and the new one is doing the exact same thing..
If the brand new one has the same problem then it’s either your shift settings in the tune or a wiring issue. Make sure your transmission harness is pinned correctly, you’ve got 12 bolts going to the shift solenoids, and your grounds are good.
I’m having a problem with my ls1 swap ! As soon as I connect my vacuum line to my brake booster engine dies on me or when I cover the vacuum like with my thumb it shuts down as well any suggestions
You need to adjust your throttle body opening to allow more air in.
For the fuel trim issue is there anyway to fix this outside of programing ?
Yes….use extension pipes or put exhaust in it.
So i just wanted to also mention something else my exhaust pipe is exteneded 16 to 18 inchs roughly from my o2 sensor given that info is it still likely this could be my issue. Note the car does run just after it gets warm it runs like ish and then when i cut it off and back on it runs like crap right away almost.
Question will this work with a ls ignition coil swap on a 92 corvette?
Hey so i have a 2005 silverado that was a v6 and i put a 2002 engine in it. Im going to do a drive by cable should i use the 2005 harness or a 2003 and under harness?thanks
Hey what’s up bro how you doing my LS swap won’t start I got power at the coils on the keys turned on position I got power acting injectors where do I have to turn the key over to see if the coil packs and stuff are getting power or just on to the on position I want to 87 Camaro third GEN
Just a quick note finally figured it out it was another ground bottom front on cross member single black outside harness not the one that goes to lights must be 5-6 different grounds wow thanks
So I have a 71’ cj5 with a 5.3 and while it’s cranking its not getting spark 90% of the time because sometimes it will get spark and try to fire up but dies agin and just sits there and cranks, it used to start with no issue and for context it has been mudding and gotten wet and after that seems to be when the problem started
#1 was my issue. Thanks bro. I’ve been fighting with this thing for a week
Glad to hear you got it figured out!
Dude you kick ass!!! I totally forgot about the 12v while cranking!! Great video!!!!
Thank you sir! If this video helped you out, please share it with others and help the channel grow!
What have connect to get 12 v while cranking
Do you have any tips like this for the LT1
Other than the video I did for the budget LT swap pan I’ve never touched one.
So it sounds to me like I’m having the number one issue you described. Did a Gen 4 swap on a 2010 chevy 1/2 ton. Did a full delete kit on dod/afm. Can’t find any ground issues or connection issues. No spark on no 1 or no 3 cylinders definitely had help to do that. The guy who did the ecm delete for the dod/afm read smog, throttle body, cam position, traction/ stable trac control codes and they wouldn’t clear. Cranks and cranks but no fire. I’m lost. Don’t know where to start. Cleaned some grounds and now only reads limited power on the dash but that’s in my shop without a reader. Still no spark.
I heard If your running it on a stand, you attach all the pink wires together and orange wires are constant hot, I did this and still isn't firing up, I got good grounds, I got spark on the plugs when turning over but won't fire up
Just put a 6.0 on my 03 gmc but no fuel is going into the injectors ? Idk if I need to change the fuel pump
Follow up: You nailed it!!! Thank you so much for helping me get my LS started!!!
Glad to hear it brother!
Can you help me out I have the same problem but I'm trying to get a better understanding of it so I can see if I was close of understanding it better..
Okay on mine I still have the V6 batter cable goes to the alternator but it's short for the V8 I add a other batter cable with a fuse in-between and ran it to the battery fuse box bolt...
Do you have to delete vats if you used the complete computer and bcm from the ls truck
Love the tips bro! You are a wealth of knowledge
Thanks brother. I’ve actually been meaning to do this one for about a year now.
Any suggestions for a good switched ignition source to use? #1 seems to be my issue
My suggestion is grab a multimeter and find one as explained in the video.
Did ls swap but it not will not crank. Does ecu control cranking? Battery and starter good.
No. That’s gonna be the original vehicle wiring, nothing to do with the swap.
Any thoughts on what camshaft and intake manifold would work well on a lm7 in a old yj wrangler? Manual shift and 4.56 gears.
Stock truck intake. Call or email cam company and fill out their vehicle info cam card to get a good cam recommendation.
@Bad Luck Garage thanks. I assume the performance style intakes sacrifice low rpm power for all top... heard good things about a trailblazer ss one though.
Yes with the exception of the FAST intakes, most aftermarket intakes make more peak power at the expense of low end power. The NNBS/TBSS truck intake is the all around most powerful factory style catherdral port intake manifold.
Got a question.... my ls swap has been running fine and all of a sudden it started missing on high rpm decel and started draining the battery and then u went to start it and now it will not start. It will hit every once and while but will not start and run . Any ideas where I should look ?
Hey buddy I done a swap my car was running fine and driving fine till one day I started it and it ran and cut off. I have a Holley terminator that I changed the relay cause it was wet and it ran again and now it's doing it again and I changed the relay but still want run and we're getting plenty of fuel
How about some to no throttle response and bad idle
good advise thanks
Amazing Video!!! I have a slightly different situation that you might be able to help me with. I removed and reinstalled my LS3 engine into the same car, 2014 Camaro SS. Everything is hooked back up but we are not getting any crank. We put the key in and we get power but when we go to start it, everything shuts off. We benched the starter and it is good to go. We will look into "checking for power at the coils and fuel injectors while we are cranking but do you have any other troubleshooting ideas we can try?
Same no problem yet but dosnt hurt to watch an get knowledge, great video
Thank you!
Can you do a video correct way to ground wire for your ls swap
Same as any car brother. I run grounds from battery to frame, body, and engine block. Then ground from engine to body. But those aren’t the grounds I’m referring to in the video. I’m referring to the engine harness grounds. There are usually two that goto the back of the heads and sometimes one at the front. It all depends on what harness you’re using.
I have a gen 4 5.3 that I pulled from a Yukon xl that I put in my 09 single cab Sierra and I haven’t been able to turn it over or even connect to the ecm. And the throttle body doesn’t open up. I ordered a brand new wiring harness hoping this fixes it and gives the engine power. Are you able to give me any word of advice when I get it re wired up?
Did a 76 Blazer 5.3 swap. Stock harness drive by wire. Runs for 3 seconds. has open stock manifolds. 02 sensors not hooked up yet. Is this why it stops? Thank you
Could be, or could be one of the other issues explained in the video.
Awesome knowledge I am 61 and I might put a 6.0 in 4.8 is 2006 and 6.0 is 2007 I am wondering if the relucter wheel on the crank may be different?
It depends. 2007 was a crossover year for the Silverado. The “classics” still had the gen3 engine and pcm while the “New” trucks had the gen 4 pcm and engines. There are several visual differences. Most notably the intake manifold is different, the gen 4 has the knock sensors in the side of the engine instead of on top under the intake like the gen 3, and the gen 4 has a cam sensor in the front timing cover. Those are just a few quick ways to tell the difference.
I’m running rich got black smoke, the stock harness I got only has one female plug for 02s other is male won’t fit the sensor, not sure if that makes a big difference or not…
I wonder if running rich makes my Edw (throthle)not work. 🤔it does turn on tho(truck)
Figured out my problem I had weird 02-07 intake and it had 36lb flex fuel injectors smh I’ll stick to the truck intakes from now on
@@Guidi815 huh..I guess it was fuel related...Im thinking mine has to do with the throttle body, harness ect..I'll give an update once fixed
@@MOE13576 are you all stock ls? Dbw I’m guessing?
@@Guidi815 yup...pretty much(ebay harness).after installing an oil pressure gauge Inoticed I had "dead" acceleration pedal...it was working just fine before this.
What about when the fuel pump wont get power
Check your wiring and grounds.
Or spark or coms
@@mickbrowne2378 same answer
Where do i get a wiring diagram
@@mickbrowne2378 Google. But you don’t need a wire diagram to check all your connections and the pins in all the connectors and make sure everything has connectivity. Also make sure all grounds are tight as stated in the video. Not just connected....make sure they’re TIGHT. Check all fuses and relays. Make sure they’re operating properly. This all falls under “check your wiring and grounds”. 👍
This vedeo help me with my swap Thanks
Any update here?:
I have an issue…crank, no start…LS1. I checked spark and have spark on ONLY cylinder #1! Any ideas? All plugs, wires, coils, and injectors are brand new. Thank you.
am doing an ls swap and i want to wire my starter relay as the factory truck donor ( 2002 chevy tahoe) Ppl wire from starter solenoid to pin 30 on relay, ground to pin 85 on relay, Yllw wire from NSS to pin 86 on relay, pin 87 not used and Ppl/Wht from NSS to fuse box but there no fuse to this wire and not connected to anything so my question is this factory relay wiring works to start the engine on or something is missing?
I have a 4th gen fbody that was v6 I swapped to ls and it’s only running one side of the motor I was wondering if you’ve came across this problem and how did you fix it
sounds like youve just got a bad connection or bad ground somewhere.
Is it normal for my 5.3 that is built putting out around 419 rear wheel horsepower..... is it normal for it to have a major sucking noise through the air filter on a 1026 Nick Williams throttle body and a 102 fast intake
Hey got a junk yard swap in a s10 no power to coils or injectors
Well you picked the right video to watch them. Hope it helps you out. 👍🏻
Hi need help I did ls swap on my 71 Camaro and it had 4l80e now I swap to tr6060 now my car crank but not starting.do you think it could be pcm setting?
Almost 100% certain.
Hey I know this is a old video but maybe I can still find help, ls swap starts then dies instantly? I have the whole original setup just in a different frame any input on where to start?
How do i go about hooking my 12 v constant ignition to my wiring harness for my Ls swap
12v constant and 12v igniton are two totally different things. 12v constant is just a battery 12v, 12v ignition was explained in the video.
Man that’s the nail on the head before I started tuning I was so dumb to how smart these pcms are or how much of a pain they are as well lol I would never think to put it in open loop I mean that’s how we tune fueling duh wouldn’t dawn on me with the fresh air so close to your o2s the STFT would freak out thank you brother GOD BLESS.
Yea we tend to overlook things sometime. If you go back and watch the exhaust video in the DR Nova playlist I was like “what the hell is going on!!??” I actually at one point mention that it could be because of the open headers but then I was like naw, it’s gotta be something else. Damn thing started running so crappy we were barely able to limp it off the trailer. They finished building the exhaust, I reset the LTFTs and BOOM it was running great. Sometimes second guessing myself all the time is a course. 🤦🏼♂️
Bad Luck Garage yeah I want to say it’s happen to me as well but I just below it off and finished assembling everything lol so I’m thinking that exactly what it was
I have an issue…crank, no start…LS1. I checked spark and have spark on ONLY cylinder #1! Any ideas? All plugs, wires, coils, and injectors are brand new. Thank you.