TPS Troubles

[RNLessley]

I have a 2000 pontiac grand prix gtp that has 2 code's (P0101 & P0121). I figured I would start with the cheap fix first and change the TPS. I did but I still get the same code (P0121). Before I start on the MAF sensor I need to find out why the bad TPS code is still coming up even though I put on a new one. I'm not a mechanic so all help and suggestions would be appreciated.

[DeltaP]

Did you clear the codes and perform a full drive cycle afterwards? Do you have a 5 volt reference signal to the TPS? It's not always the part but the circuit.

[RNLessley]

I did clear the codes but the TPS one came back. What's a full drive cycle and can I take my car to autozone to check the volt reference signal? I have never checked for a volt reference before, how would I go about doing it if autozone doesn't do that kinda thing?

[Tech II]

P0121 can cause P0101......

So, if you installed a new one, the question is, is the signal reaching the PCM?

Easy to check with a scan tool.....can try Autozone....

Just have key on, engine not running......TPS should read around 0.5 volts, and should steadily increase to over 4.0 volts as you slowly step on the gas pedal....

Do you have a high idle? Low MAP reading can cause the code, as well as a bad connection at TPS or PCM, or even a bad PCM(rare)....

Have seen mice eat harness wires in air box where PCM is located....

[RNLessley]

Your tips helped but Autozone didn't help much at all. So now the TPS is fixed but now I still get P0101 and now also get P0650. I swear if it's not one thing it's another. I can only guess that I will have to get a new MAF sensor but now what about the P0650 code? Oh by the way, before I did get codes P0446 and P0452 after I had a mechanic change my fuel filter but they haven't come back since I changed out the TPS and cleared the codes. I know I should junk the car but it's all I have for now. Any ideas if any of the codes are related or should I just start replacing things one at a time?