Compression Check: Testing and Inspection

1. Start engine and allow to reach normal operating temperature.
2. Turn engine off, then disconnect ignition module harness electrical plug.
3. Remove spark plugs.
4. Install compression gauge tool No. SST SA9127E, or equivalent, in spark plug hole.
5. Ensure battery is charged, then fully open throttle.
6. Measure compression while cranking engine. Cylinder should puff or compression gauge needle should bounce a minimum of 10 times. Do not crank engine for more than 15 seconds.
7. Repeat preceding steps for each cylinder.
8. Normal compression pressure is 185-205 psi; minimum pressure is 180 psi.