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Compression Test Spread Analyzer

Analyze Your Compression Results

Use warm-engine, wide-open throttle test numbers for best accuracy.

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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