94 Jeep Laredo Stalling

I just went ahed and replaced the EGR valve on your recommendation. Turns out, you are spot on. The car turned on and stayed running. I cant thank you enough for that information. I would like to clean up my idon a touch more however. At idol the truck often times revs from 500rpm to 1000rpm. No hint of wanting to stall, just a constant 500-1000-600-1000..... I cleaned the IAC. Should I go and replace it all together? Im getting no codes flashing or check engine light. Whatcha think?

EGR problems are common on pre '96 5.2 Magnum V8's, I'm on my 3rd. EGR valve currently (so far so good).

Please check for and eliminate all vacuum leaks before condemning & replacing the IAC, a good scan tool like the DRB Scan Tool used at the dealerships can remotely control the IAC and confirm weather it's good or bad.

But before that, let's do the simple stuff that don't cost $$$.

With the engine idling I would completely check the manifold area and all vacuum hoses & tubing (including the tubing at the cruise control unit) for vacuum leaks.

I usually do this by spraying some carb cleaner

(BE CAREFUL, THIS STUFF IS EXTREMELY FLAMMABLE)

at all vacuum hose joints , I also spray the connection where the intake mates with the cylinder heads, also check the PCV hose where it plugs into intake (the hose usually goes bad there), if there's a concern about fire you can substitute spray lubricants like WD-40 or PB Blaster for the carb cleaner.

Now DON'T soak down the top of the engine with the spray, you just want a light & fine pin-point spray at whatever connection you are testing.

What you're looking for in the above test is a noticeable change in the engines idle quality, to say it another way, if you can cause a change in the way the engine is idling by pin-point spraying a vacuum hose joint you have found a vacuum leak that must be fixed before you can go on testing.

The next thing I would do after making sure that there are no vacuum leaks is to clean the throttle body throttle plates.

Unbolt the throttle body from the engine and use a spray-on industrial strength carbon deposit cleaner like Mopar Combustion Chamber Cleaner or just Mopar CCC and an old toothbrush. The Mopar CCC can be found at any Jeep/Chrysler/Dodge dealership, and the stuff is really good at removing carbon from the combustion chamber & it's not too expensive, do a Google search on Mopar CCC and read all about it.

If the above tests & procedures don't cure the "hunting" idle the next course of action is to find someone with a good Scan Tool to verify that the computer controlled components (this includes the IAC) are all working within specs.

Good luck,
Bill