2001 Yukon

My Yukon when running the air at a stop sign will suddenly hesitate and the Volt meter will show a drop to about 10volts and then bounce back to normal. Also, when first starting the car and turning the air on the air conditioner will fan will fluctuate in speed matching the RPM's of the engine for a short time. It won't blow cold till I restart the car and it run normal. Very wierd!!!

I have the same problem with my 2001 Yukon. But I have also had some stalling problems when turning in a parking lot.

I was told yesterday that this may be caused by a faulty Air Idle Motor and I was told that it would be about $229 for the repair.

Can anybody tell us if this will fix the problem and if this is something I can do myself?

Thanks

It is most likely that the thottle plate is sticking. try to clean it with carb cleaner and a rag. With the engine off you can push the thottle plate open and clean out the carbon build up. it is usually caused by using cheap gas. I had the same problem and this cured it for me.

Check on E bay, there are a few mechanics that rebuild these things for about 100.00. Bad news is you have to send them yours, and they send you a rebuilt replacement....down time for you while its in the hands of shipper

I experienced similar symptoms with my 2001 Yukon XL. I visited a parts store and a customer told me to buy spray throttle body cleaner (its similar to spray carb cleaner) get a dry rag and spray the throttle body plate. You have to remove the air cleaner to reach it - similar to the plate on the old carbs. Spray it then wipe it with a rag. He also pointed me to some throttle body cleaner that goes into the gas tank, some red stuff that goes 1 oz for 10 gallons. He said use the whole bottle for a "shock" treatment. Let me tell you - my XL has never run so good - even after my first ride home from the dealership. The erratic idle completely stopped!

I cleaned the thottle body plate and my yukon is running strong again. All tho, it seams to remain at high RPM a little longer than normal and shifts a little stiff when coming to a stop?? Any ideas.

The original poster's problem could be the result of too-low of an idle speed and then an over-correction by the IAC (hence the surge). Like others have said, this could be caused by an accumulation of carbon or a bad Idle Air Control (IAC) motor.

If the IAC were unable to control the idle, whether it's from a sticky plate or a bad motor, it should throw a code.

You can use some O2-sensor safe carb cleaner to clean the plate and throttle body. If that doesn't work it could be the IAC motor. They get carbon-fouled too and will not seat properly (air will leak past them). Sometimes the motor just stops working. You can take it off and clean it or you can get a new one at your local auto parts store for around $100.

Jim