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Cylinder Compression Pressure

Ensure battery is fully charged and starter motor is in good operating condition. Warm engine to normal operating temperature and turn ignition off. Release fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE  . Clean spark plug recesses with compressed air and remove all spark plugs. Install compression gauge. Hold throttle in Wide Open Throttle (WOT) position. Using a remote starter switch, rotate engine 2 revolutions and record maximum value shown on compression gauge when pointer is steady. Continue test for remaining cylinders. See COMPRESSION SPECIFICATIONS  table. Install and tighten spark plugs to 15.5 ft. lbs. (21 N.m).

COMPRESSION SPECIFICATIONS

Application Specification - psi (kg/cm2 )
Normal Compression Pressure
2.0L 142-171 (10.0-12.0)
2.5L 185 (13.0)
3.0L 185-213 (13.0-15.0)
Minimum Compression Pressure
2.0L 121 (8.5)
2.5L 148 (10.4)
3.0L 164 (11.5)
Maximum Variation Between Cylinders
All Models 7 (0.5)
NOTE: Engine vacuum information is not available from manufacturer for 3.0L engine.