New to the site. I have a 01 Grand Cherokee Limited with the 4.7. My problem is after I drive awhile with the cruise on (the cruise works fine), when I cancel the cruise and driving slow in town the engine runs rough. The idle goes from 600 to 500 or less and feels like its going to die. It does this for a little while, then it clears up and runs fine. I tried driving the same distance on the highway not using the cruise and did not have the problem. Any suggestions?

 

Try looking for a vacuum leak in the cruise system. Sounds like the vacuum resivoir has to be charged again before it runs smooth.

 

Thanks for input. At least that gives me a direction to go in. I've never dealt with that type problem.

 

I believe the vacuum resevoir is underneath the battery tray. Don't quote me on that. Be careful removing the tray because there is a battery temp sensor under the battery. It tells the PCM how to control the charging rate.

 

Welcome to CF. Not sure that's your issue, but here's some diagrams of the WJ vacuum reservoir.
I'd check for any stored trouble codes. You can do this yourself, this tells how, and see the list of codes here. >http://www.wjjeeps.com/faultcodes.htm#ERASE

 

Clean the trottle body and the pintle on the idle air control motor.

 

Update. Cleaned the Idle Air Control Valve, fixed the problem. Thanks alot !!