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Engine Compression

For models equipped with Direct Ignition Systems (DIS), disconnect battery terminal connector from coil. On "Quad-4" models, Integrated Direct Ignition (IDI) cover and 11-pin IDI harness connector should be removed. On other models, disconnect "BATT" terminal connector from distributor.

Check compression pressure with engine warm, all spark plugs removed and throttle valve wide open. Crank engine through 6 compression strokes before reading compression gauge.

COMPRESSION SPECIFICATIONS

Application Compression Ratio
2.0L (VIN K) 9.0:1
2.0L (VIN M) 8.0:1
2.0L (VIN 1) 9.0:1
2.3L (VIN D) 9.5:1
2.5L (VIN R & U) 8.3:1
Compression Pressure 2.0L, 2.5L (1) 100 psi (7 kg/cm2 ) min.
Maximum Variation Between Cylinders Less than 30%.
(1) Information not available on 2.3L VIN D "Quad-4" engines.