Hood open, engine power reduced, service Stabil-Trac, etc.: Won't

[wcortesi]

RESOLVED!

It was the TPS wiring harness. As others have posted here and on YouTube, the wiring can come undone from the connectors or, as in my case, break further back into the harness.

The good news is that the dealer covered the throttle body and TPS, along with a new PCM. The bad news is that they decided not to cover the harness or 3 hours of labor to figure it out. Total bill was just over $400.

I wasn't real thrilled with that decision since the letter I have said that if it exhibits the symptoms, they will fix the TPS, and as I see it the harness is part of that system. I understand that they took a lot of their time to diagnose the problem along with the parts they threw at it, but I think GM should kick in to pay for it since it's obviously a known problem that should have been diagnosed sooner!