[Riley1717]

Glad I found this site! I need your help. I have a 2004 Grand Cherokee with a 4.7 Power Tech Engine. While driving the engine will surge 400-500 rpms. I have taken it to a mechanic and he said the computer says no codes came up. So he charged me 100.00 for a tune up. Based on what I have read it is either the TPS or the Idle Control Motor. On another site someone had the same troubles and said he fixed it by cleaning the air intake motor with Throttle body cleaner. How would I go about this? Should I try this or just replace the TPS and the idle control motor.

I sure would appreciate any help!

Thanks,

Jim

[oldfamilyguy]

if the surging is random, not just at idle, I would suspect the tps, but clean up the iac while you're at it

[kentman]

Mine seems to surge in May or June every year when it gets hot out and use of the A/C goes up. I just take off the IAC valve and clean it with throttle body cleaner. The surge goes away completely. I just did this yesterday on the WJ, and the idle is now smooth as glass, for another year at least.