I have run into this a few times and the Engine Coolant Temp sensor was the culprit. I could not find the proceedure to test the ECT in my database for some reason and I would definately recommend having it tested before replacement. Does your code reader allow you to see live data? If it does watch the coolant temp reading to see if seems to be reading correctly.
I did check for Technical bulletins that fit your symptoms and did not find any exact matches, but did see a lot of them for reprograming the Powertrain Control Module. I was working at a Chrysler dealership until June of this year and can say that corrupted data in the PCM was also somthing we came accross with some frequency.
I do have a manual on your vehicle, as soon as I find it I'll do some more research for you> I just wanted to give you what I've found, which I realize isn't much yet. Haven't forgot about you, I will be back in touch.
Saturday, October 10th, 2009 AT 10:20 AM