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PCM Issues

TymeSlayer

Tramps like us, Baby we were born to run...
3,777
2,700
Exp. Type
HPDE
Exp. Level
3-5 Years
Brighton, Colorado
While out at HPR this weekend, the gremlins I once thought had moved on, showed up again. While running through turn ten, I saw the dash light up like a Christmas tree. I mean everything. I got to turn eleven and the back end cut loose on me and it seemed like the brakes kicked in mid turn and I spun again. This happened to me last September at Hastings as well and I'm pretty sure the same issue happened while spinning out at PPIR last year. No damage done but I can't figure out what's going on. Check Brake Systems, No Fuel, Check Charging system and every other light was on and the car would not start. Now in the past I would have to disconnect the battery for a half-hour to and hour before I could even start the car. It seemed to do the trick in resetting the PCM and things would return to normal. None of this ever happened off track. It always happens in relative high ambient temperatures.I put on the Boss 302S ABS module in hopes of eliminating TC but I can't tell if it's that that's messing with me or if the PCM is just plain bad. Not only that, I had to disconnect the battery over night before the PCM would reset and the car would start. It no longer reset after waiting an hour like in the past. The NASA guys I talked with all agreed that it seems to be electrical and related to the PCM. Any ideas boys?

PS: No codes found at all.
 
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Have you changed the PCM relay? Mine was interment for about a year with no starts. Finally went out and everything was flashing and a no start. I did have codes for no communication between anything.
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
2,009
439
Southeast
Kirk:

Only happens on track, not on street duty. Happens on track with relatively high ambient temps. No PCM Codes present. My thought is to check the grounds. In my experience with Intermittent loss of ground it does not throw any PCM codes.

The first ground wire I would check is the ground wire off of the starter wiring harness. (IIRC when I replaced the headers, I repaired a ground wire near or above the starter.)

Note: it gets very hot in this location. (Just thinking out loud)

Good luck & let us know what you find.
 

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