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Up And Down Idle Problems...any Idea?

dragracer1955

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dragracer1955 Enthusiast

dragracer1955

Posted
Posted

In the past month or so I have noticed that my truck has trouble idling when I first crank it in the mornings. It is not hard to start at all, I can drive around fine and come to a stop light and all of a sudden I feel the motor just drop in rpm. It will come back up to normal and drop again. It has even stalled with me several times at a stop light or when turning. I've also noticed it only does it when the A/C is on. Sometimes it will drop so low the compressor will not kick in.

 

Is this a IAC problem or what. It's a 2000 Z-71 with the 5.3 motor in it.

 

Thanks,

Jason

98 Z71 SLT Senior Enthusiast

98 Z71 SLT

Posted
Posted

I would bet that your throttle body is all carboned up, which would result in fluctuating idle problems.

 

Don't replace any parts. Just take your throttle body off the engine, give it a real good cleaning with some old-fashioned carburetor cleaner, then install it and drive it. I bet you'll have the truck all fixed up. Remember, get that throttle body spotless.

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