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Engine Compression

Check engine compression with engine at normal operating temperature at specified cranking speed, all spark plugs removed (on dual plugs, remove exhaust side only) and throttle wide open. Ensure crankcase is full and oil is correct viscosity. With compression gauge installed, use remote starter to crank engine.

Crank engine at least 5 revolutions and record highest reading. Repeat procedure for all cylinders using approximately the same number of revolutions. The lowest compression reading should not be less than 75 percent of the highest compression reading. No cylinder compression reading should be less than 100 psi (7 kg/cm2 ).

COMPRESSION RATIO SPECIFICATIONS

Application Compression Ratio
1.8L 9.0:1
1.9L 9.0:1
2.2L Non-Turbo 8.6:1
2.2L Turbo 7.8:1
2.3L HSC & HSC MA (1) 9.0:1
2.3L OHC 9.5:1
2.5L 9.0:1
(1) Engine is High Output with Mass Air Flow meter.