Howdy fellow jeep owners, first post here. My jeep that i purchased two weeks ago with 97k on her has been idling funny. When I'm driving along, I take my foot off the gas (when shifting or slowing up) and the rpms go right down to 600 rpms causing the jeep to jerk when shifting. After it is warm and about 30 mi. later, the throttle will stay high around 2k and when you push the clutch in, the rpms cycle from 3k to 1k constantly.
First i cleaned the throttle body with carb cleaner and cleaned the IAC plunger. Then i used this cleaner called Sea Foam. Amazing stuff. The jeep ran a hell of alot smoother and was alot peppier. But the idling problem came back along with the shifting throttle problem. I then purchased the IAC motor assembly located on the passenger side of the throttle body and this has repaired my problem. It drives like a new freshly built motor. When you push the clutch in when shifting, the rpms gradually decrease to allow you shifting smoothly and no more pulsating throttle.
I am posting this to help some of you out that is experiencing this problem. The sea foam was $6.97 and the IAC was $84.00 anlong with carb cleaner at $2.00. When using the sea foam, pull the vacuum hose of the brake booster and let the motor syfion the Sea Foam into the engine. This is the best way to clean the intake.