Compression Check: Testing and Inspection

COMPRESSION INSPECTION [FS]

Warning: Hot engines and oil can cause severe burns. Be careful not to burn yourself during removal/Installation of each component.

1. Verify that the battery is fully charged. Charge it again if necessary.
2. Warm up the engine to the normal operating temperature.
3. Stop the engine and allow it to cool off for about 10 min.
4. Perform "Fuel Line Safety Procedures". Leave the fuel pump relay removed.
5. Remove the spark plugs.
6. Disconnect the ignition coil connector.
7. Connect a compression gauge into the No. 1 spark plug hole.
8. Fully depress the accelerator pedal and crank the engine.
9. Record the maximum gauge reading.
10. Inspect each cylinder as indicated above.
- If the compression in one or more cylinders is low or the compression difference between cylinders exceeds the maximum, pour a small amount of clean engine oil into the cylinder and check the compression again.
- If the compression increases, the piston, piston rings, or cylinder wall may be worn and overhaul is required.
- If the compression stays low, a valve may be stuck or improperly seated and overhaul is required.
- If the compression in adjacent cylinders stays low, the cylinder head gasket may be damaged or the cylinder head is distorted and overhaul is required.





Compression

11. Disconnect the compression gauge.
12. Connect the ignition coil connector.
13. Install the fuel pump relay.
14. Install the spark plugs.
Tightening torque 1 - 22 Nm (1.6 - 2.3 kgf-m, 11 - 16 ft. lbs.)