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Compression Check: Testing and Inspection

Check compression with engine at normal operating temperature and throttle in wide open position. Prior to performing test, disable the ignition and fuel injection system to prevent fuel from being sprayed into cylinders while cranking engine. Ensure battery is fully charged and that minimum cranking speed is 300 RPM.

Standard compression pressure is 178 psi with a minimum pressure of 149 psi and a maximum difference of 14 psi between cylinders.