I have the car mentioned above with code P2122 which reads "indicates that with the engine running, the pcm detected the throttle/pedal postion sensor/ switch D signal was lower than the minimum allowable value for a predetermined period of time." My car would be sluggish in accelaration at times and had the message "reduced engine power, service stabilitrack" with both the cel and traction lights on. My mechanic said to replace the throttle body, I used a Cardone one, and then the car was operating the same, and even turned off on me once while driving on the expressway, after I did the relearn procedure online. He claimed that he needed to reprogram it by using dealer codes which he charged me for, he reprogrammed it, and now the car seems to operate normal. This was about 5 days ago and yesterday both lights came on startup with slow acceleration. The traction light eventually turned off, along with the cel not long after, and it drives normal again. He claims i need an oe throttle body from AC Delco and says that's why my car is acting this way. Any ideas on whether or not "Dealer Codes" are necessary to reprogram the throttle body? Is all this normal? I would really appreciate it.