Thread: High Idle 2003 grand prix 3.1

The car has been idling high for a few days . These codes came up , 10128 ,P0135, PO401 ,P1635 ..I am not sure if any of these has to do with idle control .
It wants to idle around 1500 rpm and higher . I disconnected the TPS and it dropped the idle to around 900.
I took off the TPS and it had a broken spring ,I replaced it .
It still idles high , when I disconnect it , it will idle normal .When plugged back in while running it will also idle at around 900 .
If I shut it off and restart it will again idle high around 1500 too 2000 rpm .
The throttle body has also been cleaned .

Is there something I am missing or doing wrong ?

Is there a way to reset the computer to recognize the new part or a way to adjust the idle back to normal ?

thanks in advance , James

I Unplugged the TPS ,drove it a few miles with no problem . Got Back , shutdown and restarted and plugged it back up ,it again idled high .
I unplugged it ,plugged it back in while running and it idled back down to normal .
When I shut it off cranked it back up again , the Rpms was again high around 2000.

The TPS is new and seems to work only when it wants to .
What am i missing here ?
Any clues or suggestions ?

Have you looked at the IAC? (Idle air control valve)