Hey all,

I noticed just recently when the my 06 Jeep Grand Cherokee sits in park that it'll have a weird idle happen. Basically i'll notice the idle will fluctuate and seems to go down to roughly 500 RPM's before the car tells itself to bump the RPM's back up to ~650-700 RPM's;. Just out of curiosity, should I be concerned about this or is this somewhat normal? I haven't had any stalling issues and haven't noticed it drop below 500 RPM's, but figured it was something potentially new that I noticed it was doing. If it makes any difference, I only have the AC running on cold and I haven't gotten any CEL's as of yet.

I appreciate the help!

 

The 2004 I drive stays at basically 700rpm the whole time when it is idling. Therefore, I would notice that as an unusual change if it were to happen like that on mine. Yours is all different though.. New model and new engine from the WJ designe like mine. I wonder if someone who has that model will say?

You could clean up the IAC (Idle Air Control). The IAC helps to run the Jeep when at idle - with air control. At 10+ years old vehicle it is certainly likely that the IAC is now all covered in carbon, and it might not be working at optimum capacity. It is super easy to clean.

Cleaning the throttle body at same time is how it is done best. The IAC is attached to the throttle body. I would clean the IAC (and throttle body) to see if that changes it to a more steady idle. It would be a good thing to do either way.

 

Cleaning the IAC should be part of normal maintenance and done periodically.

 

The only symptom I had with the dirty/failing IAC was I had lost high idle during initial start up in cold weather. Otherwise you'd never known anything was amiss. Of course it would have gotten worse.