The PCM issue I mentioned here is now fixed. I'll give a quick explanation.
For the past several months my car has stalled while driving. In the beginning it happened during the warmup cycle on cold (20f) days, either while idling in the driveway or driving on the highway. This was maybe once a week or every two weeks. It ran perfect until it happened, and afterwards the vehicle acted as if nothing had happened (no MIL/CEL, no DTCs*).
With the OBDLink ScanTool I was able to see that things weren't quit right; all of the OBD monitors had been 'reset' and the PCM indicated 0 miles traveled since codes cleared. Here I found another module on the OBD-II interface - I think it is the TCM - and this indicated a different mileage since 'codes cleared'. Infact the TCM showed as having a code logged against the PCM - U0100 / lost communications. This was a soft DTC in the TCM, and the PCM ignored it.
As stalling got worse, I eventually had the MIL light up with a set DTC. This 'said' the PCM detected a TCM error and had generic P0700 transmission codes. The OBD-II freeze frame was interesting; the engine RPM was 0 while everything else was normal. As the stalling got worse, there was some variation in codes and eventually the PCM admitted to a U0100 DTC, but would easily 'stall' again and come up with no DTCs found.
During this lots of things went out..things that the PCM controls. First the motor would stall (and things dependent on having engine RPMs had issues like power steering, power brakes, the AC compressor) - the deceleration was pretty severe. Cruise control would reset to having the light off. Headlights would dim as the alternator control on the PCM went out (the RPMs dropping probably didn't help either). The PCM and TCM would refuse to communicate after some occurrences - I could sit in 'D' with no power delivered because the TCM wouldn't go into gear (never had a 'limp mode' event happen though). Meanwhile other things worked...heated seats, radio, etc.
None of the local dealers (within ~200 miles, that is a population of 1 chain) would diagnose the problem as a PCM issue despite going in with this problem occurring several times. They did offer to start with replacing the TCM for $800+labor before letting me keep it in their shop...but I walked away from that 'deal'. They shot down any mention of 8yr/80000mile federal emissions warranty covering the PCM by saying they wouldn't diagnose my U0100 and P0700 DTCs and drivability issue as a PCM issue and that I would pay for all of the parts they shove into my car trying to fix it (they wanted to start with a $700 TCM + labor). There was also talk of me paying 'their retail' for a new PCM if I ignored their diagnosis with little recourse to be reimbursed if it fixed the issue... I walked out and eventually bought a rebuilt PCM online (~$230 + I ship my old one back). And it works great
In short: With those issues behind me, I hope to get hacking soon
