I know Idle issues are a pretty common thread. My current issue is in my 90 automatic 4x4 Laredo the idle jumps to 1500 rpm when I'm in park or neutral. When in drive it drops down to normal, accept sometime it stays high around 1000rpm. Lately it was hit n miss, but the last couple days it has been pretty constant. The tps was good last time I checked. Wondering if anyone else has had this issue. Thanks in advance.

 

Oh yes many times, which tips of Cruisers have you done so far? I posted the link for you.



https://www.cherokeeforum.com/f51/cr...x-tips-153657/

 

No argument with starting with ground checking/refreshing. My 90, the plug for the IAC there on the TB plugs down such I think it got some moisture in there. I suspected the IAC because usually shutting down, then restarting cured high idle. For me, just cleaning the plug at the IAC solved it.

 

I went through cruisers list pretty thoroughly when getting it to pass smog back in march. Including adding grounds where specified. She passed with "0" emmissions. Even the smog tech was impressed. Killing the engine and restarting has worked in the past. But lately not. Once I thought the lever for the gas petal just gets stuck, but that's not the case. Haven't had the chance to really dive into. Just wanted to see if anyone tried something out of the usual renix diagnosis. If I have time this Sunday ill start poking around to see what I discover.

 

Cleaning the iac takes seconds, though she was clean last I looked. Decent place to start I reckon. Think I got some extras from pick n pull, in case. Thanks u guys. Funny, my two year old knows the word jeep. Everything else to him is just a car.

 

In my case, with an identical "sweet" of symptoms, it was just the plug on the IAC not making a good connection. I cleaned the IAT when it first acted up. Was after it came back I figured out it was the contacts. (and yes, I thought it was the floor mat also.

 

Check the intake manifold bolts. If they are a bit loose you'll have a vacuum leak and high idle.

 

intake manifold leak was my problem.

 

All good advice here. Check those things.

Your TPS is probably taking a dump.