high idle on 98 cutlass

hi i cant get my car to idle below 2500 it came out of nowhere the car has never had any problems. the high idle is smooth and constant. heres whats going on:
1.replaced the tps and the iac because of dtcs. cleared codes. no codes have come up since.
2. gear indicator light wont shut off after car is off
3.cruise is engaged light stays on while running
4. theft light is on while running but car starts no problem
5. checked vacuums. ok
all these have never shown up til my idle problem showed up its drivin me crazy please help

tom

Which engine?

sorry 3.1

I have not experienced this first hand, So, I cant say for sure. But, by the symptoms listed here, it sounds like your cpu is going bad. Like I said, I dont know for sure. Other thing that may or may nto cause this, Possibly a bad ground somewhere dealing with the computer, lose wiring on the computer. Good luck.

Make sure there is no binding in the linkage and throttle body, post back, also did this start after changing the tps?

Did you new IAC have a new o-ring on it?

Whats the status?