Operation CHARM: Car repair manuals for everyone.
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Compression Check: Testing and Inspection

1. Start and warm engine to normal operating temperature.
2. Turn engine Off and allow exhaust manifold approximately ten minutes to cool.
3. Remove all spark plugs, then disconnect primary wire from ignition coil.
4. Connect a compression gauge to No. 1 spark plug hole.
5. Fully depress accelerator pedal and crank engine, record maximum gauge reading.
6. Repeat steps 4 and 5 for each cylinder.
Compression pressure: 1,079 - 1,471 kPa (156 - 213 psi) at 270 rpm
7. If compression in one or more cylinders is low, pour a small amount of engine oil into cylinder and recheck compression. Check results as follows:
a. If compression increases, piston, piston rings, or cylinder wall may be worn.
b. If compression stays low, valve may be stuck or improperly seated.
c. If compression in adjacent cylinders stays low, cylinder head gasket may be defective or cylinder head distorted.

8. Connect ignition coil, then apply suitable anti-seize compound to spark plug threads and install plugs.
Torque plugs to 15 - 23 Nm (11 - 17 ft.lb.)