2002 ls1 with engine problem

**jsmith564`** · 07-20-2011, 02:30 PM

ok i have a thread in the general help section "vibration" it has lots and lots of info about whats been going on. however after months of tinkering with it and now recently installed a rebuilt transmission, flex plate, stall converter, swapped coils and the dampener, replaced plugs and wires, o2's, installed poly mm and trans mount it's not changed anything as far as finding the problem.

i noticed the engine had a vibration to it when i bought it. assuming it just needed general tlc. so long story short after doing all the above it's not changed a thing. the transmission was slipping so i went a head and had that work done, the flex plate was trash also. the guy who done the install said he did some logging on the car and that it showed it's misfiring on all cylinders. the car was bone stock when i got it. i'm sure i'm leaving out a lot of info. but i'm going to pick the car up this weekend. i have not give up yet. please advise!!!!!!!!!!!!

**transamtom** · 07-20-2011, 02:55 PM

You have a 2004 GTO as your car in your sig is the 2002 engine in a different car?

Is it stock? LT Headers? Tuned?

A misfire on all cylinders sounds like a cam sensor or something similiar.

**transamtom** · 07-20-2011, 03:04 PM

I just seen your other thread and I am going to read it.

**jsmith564`** · 07-20-2011, 03:09 PM

thanks man. yea the car is a 2002 camaro ss ls1 a4 was complete stock when i bought it. it was mistreated, own by a high school boy. i'm all ears man!

**transamtom** · 07-20-2011, 03:17 PM

Originally Posted by jsmith564`

thanks man. yea the car is a 2002 camaro ss ls1 a4 was complete stock when i bought it. it was mistreated, own by a high school boy. i'm all ears man!

Could the timing chain be stretched? or have jumped a tooth or two?

My LT1 chain was stretched and it ran a bit rough until I got it swapped out.

**transamtom** · 07-20-2011, 03:21 PM

One more thing,if the car was abused by some punk ass kid you should do a compression test on all the cylinders that could cause a misfire if they were all low.

**jsmith564`** · 07-20-2011, 03:31 PM

180ish psi on the compression. i didn't do a leak down test. not sure on the chain. it having 80,000 miles it might be due for one. would the computer throw a code if the cam sensor was bad? only codes that come up are from the air system i removed.

**transamtom** · 07-20-2011, 03:58 PM

Originally Posted by jsmith564`

180ish psi on the compression. i didn't do a leak down test. not sure on the chain. it having 80,000 miles it might be due for one. would the computer throw a code if the cam sensor was bad? only codes that come up are from the air system i removed.

PO341,PO342 and P0343 would be the codes for the cam sensor.

At 80,000 I doubt the chain is stretched,my 124,000 mile engine is still going strong with no probs.

I am going to say its a bad camshaft sensor or crank sensor as they are the only things that control all the cylinders.

If the PCM is getting wrong info things can get wacky in a hurry.

**jsmith564`** · 07-20-2011, 04:39 PM

i agree. i took it into an lsx shop and he was puzzled. he was not a big shop, but pretty damn good with them, but it stumped him. so whats you're suggestions? whats my next step?

**transamtom** · 07-21-2011, 01:16 AM

Originally Posted by jsmith564`

i agree. i took it into an lsx shop and he was puzzled. he was not a big shop, but pretty damn good with them, but it stumped him. so whats you're suggestions? whats my next step?

You have replaced just about everything else on the engine,whats 2 more sensors in the grand scheme of things?

I say get the Cam Sensor and Crank Sensors swapped out with new ones.