Originally Posted by diablo2112

Yeah! I believe the problem has been found and resolved. It's been a full week, and the car has been flawless. No codes, no limp mode, no issues. After 3 months chasing this problem, I've got it fixed. A couple of comments.

1) I replaced nearly everything possible in the throttle circuit: battery, accelerator pedal, throttle body, air filters. The only things remaining were wiring and the ECU.

2) reading out all the parameters on my OBD reader gave me a critical clue: the accelerator pedal circuits were labelled "D" and "E" and the throttle body was labelled "B". This helped isolate the problem to the pedal-side of the ECU (recall, my code mentioned circuit "E"). I did this late in the process, and could probably have saved myself the headache of replacing the throttle body had I done this sooner.

3) Installing a pedal commander box was helpful. It isolated the problem to between the box and the ECU. In other words, it was either the ECU or the wiring. And, the pedal commander is awesome. Seat-of-the-pants feel of the car is totally changed for the better.

4) Approaching this issue methodically enabled me to finally isolate the problem to a plug that had a bad connection. This plug wasn't anywhere near the other components. The wiring diagrams and plug-quick-reference chart were essential here to finding the location.

5) A more general observation is our cars have hundreds of plugs and the connection CAN go bad. I think many of the intermettant problems reported may be due to this issue. The lesson here is the wiring diagrams are your friend. If you get a similar problem, look for common plugs in the wiring diagram and inspect/clean as necessary. Clearly, these connections/plugs can go bad over time, as mine did.

Excuse the long thread here. My 3-month adventure is resolved. I have a box of spare parts to show for it, and the satisfaction of fixxing it myself without much more cost. Finally, the title of my thread is now correct.