Hi all, I have a 2008 Jeep GC Limited 4.7L regular fuel. Rough Idle, Bad acceleration.

Try a good fuel system like Techron. Is the check engine light on?

A lot of miles? Hard usage? Maybe the camshaft chain jumped timing a cog or two. With all that trouble, hard to believe it doesn't show a fault code like F_O_R suggested.

Yep, forgot, The engin light is on and it is flahing. Even after I hard booted the puter!

Well golly! Without the trouble codes we can only guess. The light is not the problem. It is the messenger.

165, 000 miles, I do all the work on it. Been great til last week. The throttle body made it better but today I couldn't get it over 20 mph. I appreciate all ideas. Ill be back at it again tomorrow.

Yep that is why I am going nots, No codes came up after the throttle body. The IAC code came up, In these the whole system is encased in the T B. Ridiculous. I am hitting it from all angles, Its gotta be something . So I go for the TPS... It doesnt have one. Who invented this mess? lol

Well it is a Jeep. Condolences. If the light is flashing but there are no codes the computer may be at fault.

I have one last thing.... could it be a plugged or failing fuel pump. My last shot before take it somewhere. It keeps running rough and never cuts off. I did as much as I could for an arm chair mechanic. Thanks for your input peeps!

Check your fuel pressure.

ya tomorow Ill get a guage and hook er up. Thanks.

Any updates? I have 2007 Gr. Cherokee with 3.7L but guess what, it must be a late year model because it has the 2008 engine. ETC, no IAC, and I have a code for IAC unexpectedly high RPM. Weird. But I already have a new ECM and plugs, coils etc. I think it's probably worth it to take her in and have the throttle body recalibrated by the dealer. At a certain mileage, that's recommended. Could help clear things up for the both of us. If I do it, I'll let you know how it works out.