Ok I have a grand Cherokee with the 4.7 and sometimes it doesn't run great it will sputter and tack out at 3000 rpm and sometimes die at a stoplight or run at 400 rpm. My question is I think it is the idle control valve cause it would make sense. If not what else would be causing this.

 

It revs up to 3000RPM without your foot on the gas?

 

Not on its own but when im passing another car and hit the gas it does and it sputters like it's not getting air or gas

 

Check it to see if there are any fault codes stored. Here's how to do it yourself and a list of the codes: >->http://www.wjjeeps.com/faultcodes.htm#ERASE

 

I don't think it's a IAC issue, the IAC only controls the idle speed.

 

Could also be the catalytic converter plugging up. Not gettin any air out will cause poor idling in some cases and will restrict engine rpms like that.

 

Usually I'd agree on the catalytic converter but who ever had it before me cut a hole right in front of it cause im sure that was the issue before

 

Will this work on my XJ?

 

The codes that popped up are p 0108 and p 0132

 

P0108 code relates to the MAP sensor. I had experienced similar symptoms to what you've described in one of my BMWs. The problem was related to a bad MAF (essentially the same thing as a MAP as far as I can tell). An easy way to test the MAF on a BMW is to unplug it which forces the system to use default parameters. I suspect the same would be true of the MAP sensor on the Jeep.

P0132 is related to the O2 sensor. Something I'm not surprised to see given your post mentioning the previous owner drilled a hole in front of the cat.

 

Thanks that's what I needed to know until next time . Which could be tomorrow but I love my jeeps