Ok, so I have an 02 gtp. 3.4 mps, 180 t stat, pacesetter headers, cai, ported t body and zzp pcm. I've had it for a year and had no problems. About a month ago maybe 5 weeks, it started stuttering, losing power and missing bad if i gave more than about 50% throttle input. It would only happen once the car was up to temp, around 180-195 degrees. i would have to back off the gas a little and it would be fine. IF THE CAR WAS STILL RELATIVELY COLD, NOT FULLY UP TO TEMP IT WOULDN'T MISS A BEAT. Not a single sputter even at WOT full boost. This is the most confusing and I feel most important clue. No check engine light came on and no codes stored. 2 good techs in my area and myself have been trying to figure out the issue since then. One hooked the car up to his real time scanner and showed the misfire was only on cyl 2 and there were over 500 in a 10 minute period. Still no codes present however. This past week, it's gotten worse. Now it doesn't matter if the engine is cold or hot and I can only get a third of my pedal travel before it starts doing it bad. I can barely get moving sometimes. I've ruled out the coil pack, plug, wire, injector, crank sensor, and just put a new zzp pcm in thinking it has to be that. The replaced PCM has improved this condition but it may only be because the pcm is relearning. Please help. This is a huge problem thats getting worse and I have no clue from this point. We dont think its mechanical because of the inconsistency.
