2500 rpm idle when cold

I saw a thread a long time ago about high idle, but I can't find it.

My 89' five speed will occasionally start and idle at about 2000 rpm's and progressively get higher until it reaches about 2800 rpm's. It will continue for several start cycles and for no known reason it will go away. If I drive it while the rpm's are up, the jeep will continue to accelerate until the rpm's reach 2800.

I thought it was a vacuum leak, but if it's a vac leak the condition should be consistent, correct?

I almost forgot, the last time it did this, I unplugged the TPS and the connection next to the TPS (IAC maybe?) and there was no change.

Can someone please help, thanks
Darin

First, have you tried the advance search feature? If the AS feature doesn't find it you can also try using Google, I have found numerous threads on here via Google searches.

Second, did you test your TPS with a multimeter yet? What were the readings?

As for consistent on the vacuum leaks--maybe yes, maybe no. When cold the fuel mixture is richer, which could mask the vacuum caused lean condition, but as the engine warms up and the mixture is leaned out the vacuum leak would have a greater effect.

i had the same issue with my 89
auto.
I read all the post about how to clean and add super duper ground wire to the existing system.
With out wanting to get too involved, i unplugged the Idle Motor and it never happened again.This isnt a FIX, but i never had the same issue again.
Mine got so bad, that the brakes didnt wanna bring the jeep to a complete stop once it got going.
After a while, it would start with the idle where it should be, then outta nowhere, it would jump to 2500 rpm while i was driving down my neighborhood street.

thanks for the replies. I'll measure the TPD voltage and disconnect the IAC motor.

Thanks
Darin