the tranny.... thats what my dealer and i are thinking...
i just got mine back from the shop (was in for two weeks) I was having limp mode just about every time i "stepped" on it. I did have a leak on my tranny cooler which they replaced (under the 70/7 yr powertrain) and i havent had any probs since...
the real funny thing was the tech that was working on my car said "you know that code you got from not putting the sensor on the right way when you changed your air filter... well im not really saying this BUT you should look on-line somewhere and see if there is something to hook up to your computer to trick the puter into thinking the sensor is plugged in your really dont need it"
I just played it all off and said "really?? wouldnt that hurt my motor??" and then he pulled me out of the shop and told me just about everything we have said on here! it was true greatness!!!!