Compression Test Results: Are Your Numbers Good?
Analyze Your Compression Results
How to Read the Results
Compression should be fairly even across cylinders. A large spread suggests a mechanical issue like worn rings, leaking valves, or a head gasket problem.
- Up to 10% spread: Usually healthy.
- 10-15% spread: Borderline; watch trends and symptoms.
- Over 15% spread: Investigate further.
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