Idles high

2003 JEEP GRAND CHEROKEE
132,000 MILES • 4.7L • V8 • 4WD • AUTOMATIC
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MTDEW152
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  • 1 POST
I put a coil pack on cylinder eight and eight new plugs on. Also an idle air control. Now it runs at 2,000 RPM's. What is wrong?
Jul 28, 2018 at 1:31 PM
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STRAILER
  • CAR REPAIR CONTRIBUTOR
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First did you install OEM plugs? If not change them all out. I know it sounds strange but factory plugs have a particular resistance which will change the spark timing. Also, I would service the throttle bore. Here are guides that should help:

https://www.2carpros.com/articles/engine-idles-too-high

and

https://www.2carpros.com/articles/throttle-actuator-service

and

https://www.2carpros.com/articles/how-to-change-spark-plugs

Please run down these guides and report back.

Cheers, Ken
Jul 29, 2018 at 4:41 PM
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