OK, so I did just as was suggested, and probed the voltage coming from the TPS rather than measuring the resistance. Here is what happened.
1. Adjust TPS to get voltage specified in directions, 0.70 at idle, 4.3 at WOT.
2. Reset PCM
3. Turn on igniton for 30 seconds
4. Turn off ignition
5. Start engine.
After I started the engine, the check engine light came on.
I checked the values of the TPS on my mom'* '02 Grand Prix. They are 0.46 at idle, 4.06 at WOT. I adjusted my car to these values, reset PCM, no check engine light.
Any ideas why I am having such a hard time with this?