the other day i noticed my jeep got abnormally louder than usual. (i have it straight piped from the cat back) no big deal right, just blowing the crap in the cat out which it was. however when coming back from some wheeling i was doing about 75 and all of a sudden my check engine light comes on. look at the gauges and nothing is wrong. once i get home i run the code and it comes up for a IAC. put it off, put it off until one day the RPMs are really high and i dont want to drop it into gear. so i go buy a new one and install it. code goes away for a min once cleared and now the jeep wont even hardly idle unless you hold your foot there, and then the check engine light comes back with same code. so i was thinking the tps went out on it to. bought one of those and installed it as well. well it didnt work. so i was poking around at my work (chrysler proving grounds) and people are telling me a few different things. one my PCM needs to flashed. two i need a new PCM. three there is something far more serious, like a chassis short or something. any and all input is welcome,another few things to add to the situation is after this check engine light when my left blinker is on it always turns the right one on so i have hazards on in the back. another item is my cruise control wont work. i replaced a clock spring and checked all voltages, vacuum, and even the button. im out of ideas. once again any and all help appreciated.

 

Make sure the wires connected to your IAC are not damaged, check for a vacuum leak because that will cause some of the high idle issues you state as well. Make sure your battery good, that could cause stalling if it is marginal. Those are all free checks, before you throw more parts at it.

 

they seem not to be and everything you asked appears to be alright. im getting all the right voltages to the IAC.

 

I know my my issue relating to stalling if i didn't keep a little throttle at all times was because of the marginal battery, and is a very common problem. High idle is a sign of vacuum leaks, and cruise control relies on vacuum to operate as well. Not familiar with how exactly the cel is being thrown for you, so i wont make comments there. If you turn the cruise on, does the light turn on but just doesnt work when you try and use it?

The vacuum ball behind your front bumper might be damaged or missing as well. A tiny crack in a vacuum line is all it takes and can be hard to find. Someone should come around with a bit broader area to look at, but you shouldn't be looking at the worst case scenario quite yet.

 

hmm well my battery has been low lately, so that could have something to do with it stalling. ill try there first to fix that issue. the high idle is fixed now with the new IAC but i still have a MIL light for that. ive gone around poking around with my vacuum tester and everything seems to be maintaining pressure fine. and in reltaion to the cruise control; when i hit the on/off button yes the green cruise light comes on and the servo on the cruise kicks on. when you go to set the cruise is where i have the problem. ive tried new button as well and nothing appears to be working. ive thought of the idea maybe the speed sensor, however my speedo works fine.

 

From what i've read the #1 cause of the cruise problem when the lights come on normally is the servo itself. I don't know the proceedure for testing it tho. :/

 

vacuum line to storage ball behind front bumper been checked

 

I think I did not 100% sure but ill check it tonight and post what I get

 

Vacuum can tested 100%