High idle rpm

[kamileon]

I have an 02 kj with 125k miles. Never any major issues other than just rebuilt the transmission. Recently it started to die when I stop and put it in park. This has only happened twice. Now when I cold start it it has a high rpm, around 2000. It drops to around 1000 and then jumps back up. Once the engine warms up it stops, or if the engine is warm when I start it it doesn't happen. Any ideas what the problem may be. Thanks for the help.

 

[uss2defiant]

could clean the IAC and throttle body.

http://www.jeepkj.com/forum/f196/2003-jeep-liberty-sporty-idle-problem-48728/

 

[kamileon]

could clean the IAC and throttle body.

http://www.jeepkj.com/forum/f196/2003-jeep-liberty-sporty-idle-problem-48728/

That was my plan. Was just curious if it could be anything else failing.

 

[uss2defiant]

I had that happen to my jeep on occasion as well.
Don't think it's anything to call for concern.

 

[MarkJ]

Vacuum hose off or cracked?
Mark

 

[LibertyTC]

The IAC controls the idle and generally builds carbon worse than your chimney!
You will probably find that the port and IAC spring is really gunked up!
I only clean the IAC with the pintle side down, use a tooth brush & Carb cleaner if it is really bad.
Throttle body cleaner you can try as well, but often it is just not strong enough to really get the port clean.
I sprayed carb cleaner onto precision tip Q-tips to get the outside hole/ mating surface spotless.
Also check the throttle plate to ensure it is clean and freely moving open to closed position, and not binding anywhere.

 

[mu2bdriver]

Wife had the same problem and a good cleaning of the throttle body and a new iac solved the problem.