What is a compression test and what does it mean?

Sun Valley Auto Repair • February 9, 2023

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A compression test is a test used by a technician to verify the integrity of an engine. The compression test uses a pressure gauge to measure the amount of pressure each cylinder in an engine is capable of producing. In other words it is a way for the technician to rule out or verify if a rough running engine has a mechanical problem or an electrical problem. If the cylinder cannot produce enough pressure it will misfire and the engine will simply not run correctly. If an engine fails a compression test further testing or tear down may be needed to find the root cause of failure. In most cases if an engine fails a compression test the engine will need to be replaced or rebuilt.

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