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Compression Check: Testing and Inspection





INSPECTION
1. Check that the battery is fully charged. Recharge it if necessary.
2. Warm up the engine to normal operating temperature.
3. Turn the engine OFF.
4. Remove all spark plugs.
5. Disconnect the ignition coil connector.





6. Connect a compression gauge to the No.1 spark plug hole.
7. Fully depress the accelerator pedal and crank the engine.
8. Record the maximum gauge reading.
9. Check each cylinder.





10. If the compression in one or more cylinders is low, pour a small amount of engine oil into the cylinder and recheck the compression.

(1) If the compression increases, the piston, piston rings, or cylinder wall may be worn.
(2) If the compression stays low, the valve may be stuck or seating improperly.
(3) If the compression in adjacent cylinders stays low, the cylinder head gasket may be defective or the cylinder head distorted.

11. Connect the ignition coil connector.
12. Apply antiseize compound or molybdenum-based lubricant to the spark plug threads.





13. Install the spark plugs.

Tightening torque:
15-23 Nm (1.5-2.3 m-kg, 11-17 ft-lb)