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View Full Version : WTBorrow: LS1 PCM



Alien
03-28-2012, 07:58 PM
Yes, the racecar is more reliable than the daily driver.

Does anyone have a spare LS1 pcm I can borrow to rule mine out? I have an '02 LS1 6spd T/A.

It is dying pretty consistantly now after about 10 minutes/4-8 miles. Left us stranded twice. I've let it idle in the driveway and it dies in 10 minutes. Drove it (twice around the block for a few minutes, come home let it idle for 3-4 and then it dies. It somewhat randomly will restart, havn't figured out the pattern, and don't want to simply throw parts at it.

TIA.

BryanL
03-28-2012, 08:11 PM
I have a tuned one you can try but I doubt that is your problem. Let me know how I can help. Any codes?

Alien
03-28-2012, 10:28 PM
No codes. Fuel pressue was good key on, and didn't drop at all when cranking (I assume that means injectors arn't pulsing). The fact that it dies after it's running tells me it's not VATS/PATS or whatever the LS1 security is. Checked the grounds that I could (one/two on back of drivers head feels tight, can't get a wrench on it). Checked wires near PCM and CPS for fraying.

When it does restart, it's almost random. Waited 24 hours, still didn't start til I wiggled some wires near the PCM. Another time a few minutes after it died, swapped IGN and Starter relays and it starts. Tried that same thing tonight, no dice. Toight, waited a few hours, touching nothing, it starts.

Most things I can think of that would cause it to die won't 'fix' themselves, or would cause it to run rough/bad. May throw in a new Crank Position Sensor or find someone with a scan/tuner before trying a PCM swap. I'll let you know.

edrock96GT
03-29-2012, 06:41 AM
Hmm. Does it sputter and die or just die? The only thing I can really think of is your fuel pump possibly overworking and shutting down after 10 minutes (had that problem with a Suburban once, only did it for a day though).

Alien
03-29-2012, 07:04 AM
Headshot. Just dies.

Reason I ruled out pump is that it still had 55psi key on, and didn't start, pressure stayed at 55.

Pranav
03-29-2012, 09:49 AM
Check the positive wire going to the PCM, like really check it.

BryanL
03-29-2012, 04:21 PM
Certainly sounds like wiring when you wiggle some wires and it starts. The VATS generally kills the car in a few seconds. I have a VATS bypass module you can try too.

Or just let me know how much you want for the whole car.

Alien
03-29-2012, 04:30 PM
At times I think that as well. And then there's the time when simply hooking up the fuel pressure guage, then cranking will start the car. Or swapping relays will start the car. ARG!

Car is being sold once it's fixed to my father-in-law. I really really don't want to get rid of it, but we have too many cars to justify keeping it. This way it'll stay in the family so I can get it back later :)