Will the IAC valve make it idle rough?
#1
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Year: 1997
Model: Cherokee
Engine: 4.0 Liter
Will the IAC valve make it idle rough?
My jeep runs great everywhere but at idle. At idle it feels and sounds like its missing. I have checked plugs, wires, cap and rotor. All good. Ideas welcomed.
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#7
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Year: 2001
Model: Cherokee
Engine: 4.0
You could have a valve not sealing completely. Worn, carbon...etc.
Timing chain could be stretched. Lots of things can cause a rough idle.
Have you done a cylinder balance test?
What year is your rig?
Timing chain could be stretched. Lots of things can cause a rough idle.
Have you done a cylinder balance test?
What year is your rig?
Last edited by ETexas XJ; 12-22-2011 at 10:25 PM.
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#8
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Year: 1993
Model: Grand Cherokee
Engine: 4.0L Laredo
Idle Air Control Valve.. clean it, but don't put any 'twist' on the pintle. I think I read that's bad. You might also spray some starting fluid around the engine to look for vacuum leak
#10
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Plugs, wires, cap and rotor are due to be replaced every 30,000 miles. When was this last done?
#11
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
Do a compression test and a cylinder leak down test if you can, you may have a weak cylinder. How many miles on this rig?
#13
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Year: 88-87
Model: Cherokee
Engine: 4.0
check 02 sensor
Last edited by dotyjeep; 12-23-2011 at 12:34 PM. Reason: more info
#15
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Year: 1997
Model: Cherokee
Engine: 4.0 Liter
Well, I think I found it. Only 100 psi in cylinder #1. Still runs good, just has rough idle. Looks like a valve job is in my future. Bummer.
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