2002 Mitsubishi Montero

Engine Performance problem
2002 Mitsubishi Montero 6 cyl Four Wheel Drive Automatic 73000 miles

My 2002 Mitsubishi Montero Limited began hesitating and loosing power while at idle at a light. It has a little over 72500 miles. I recently had an o2 part replaced. What could make this vehicle have such a problem, before I drop it off at the dealership?
February 28, 2008.

Could be a bad PCV valve, or EGR vavle plugged.

It could even be dirty fuel injectors and fuel filter and bad plugs and wires if not replaced recently.

May be the IAC module, unplug it and run it if it runs good then the IAC is bad.

Feb 28, 2008.
Thank you blackop555 for your response. I greatly appreciate it. I'll will take this info to the dealership for their review. A 2003 vehicle with close to the same mileage was in their shop with it's owner complaining of the same problem. They could not find anything wrong with it or mine. Or, they could not mimic the problem for further investigation. I left it with the dealership from Fri to Tues. Since home, I haven't been able to get the problem to reoccur. The fuel filter, I'm told, is in the the fuel tank and never goes out on this model. The alternator and starter was checked as well as the fuel injectors. Nothing found. Point and plugs may need to be checked but I was advised that the hesitation and lose of power at idle is not a cause by the electrical system. What is an IAC module? The computer should pickup a failure like that I believe but I'll challenge the repair service at the dealership. But thanx again. Let me know what this IAC is and provide any info you have on this matter. Greatly appreciate your time.

Mar 5, 2008.
IAC is the idle air control valve, it limits the amount of air going into the engine therefor setting the idle.

It is what makes the vehicle run faster on cold start ups then slows down when it warms a tad.

Also the fuel filter will go out it isnt invincible! Theres none inline fromt he tank to the engine?

Sometimes the fuel pump relay can solve this.

Mar 6, 2008.