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GMC
C1500
Engine
Symptoms
Rich
Third cylinder is missing and it is running rich?
1998 GMC C1500
305,000 MILES • 4.3L • V6 • 2WD • AUTOMATIC
BUCKDM
MEMBER
1 POST
3rd cylinder is missing and it's running rich?
Oct 6, 2023 at 3:26 AM
STRAILER
✓
Experienced Mechanic
55,542 POSTS
If you have a misfire the system thinks the engine is running lean so it will increase the fuel input to its max. So, we need to fix the misfire and that part should go away. Let's remove the spark plug for inspection and replace it if needed.
This guide can help:
https://www.2carpros.com/articles/how-to-change-spark-plugs
If that does not help let's do a compression test.
https://www.2carpros.com/articles/how-to-test-engine-compression
This guide can help as well:
https://www.2carpros.com/articles/engine-misfires-or-runs-rough
Please go over these guides and get back to us.
Oct 6, 2023 at 3:46 AM
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