2001 GMC Sierra ruff at idle

2001 GMC SIERRA
200,000 MILES • 5.3L • V8 • 2WD • AUTOMATIC
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HAROLDBYRD
  • MEMBER
  • 1 POST
when the engine is idling it misses ( runs ruff).
Feb 6, 2015 at 7:03 PM
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WRENCHTECH
  • ✓Experienced Mechanic
  • 20,761 POSTS
First check the computer for stored codes.

How does it run when " off idle"?
Feb 6, 2015 at 10:26 PM
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STRAILER
  • ✓Experienced Mechanic
  • 55,214 POSTS
It sounds like you have low compression in one or more of the cylinders, lets do a compression test here is how in the guide below.

https://www.2carpros.com/articles/how-to-test-engine-compression

If the compression is okay I would roll in a new set of spark plugs.

Spark Plug Type .................... Denso: PTJ16R15

Please go over this guide and get back to us.
Jul 17, 2024 at 10:53 AM
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