Cylinder Compression Pressure

Ensure battery is fully charged and starter motor is in good operating condition. On 2.4L, disconnect ignition coil connector. On 4.0L, remove coil rail assembly to access spark plugs. On 3.7L and 4.7L, remove coil on plugs. Remove Auto Shutdown relay from Power Distribution Center (PDC). PDC is located in engine compartment. On all models, clean spark plug recesses with compressed air. Remove all spark plugs. Remove fuel pump relay from PDC. Install compression gauge. Hold throttle in Wide Open Throttle (WOT) position. Using a remote starter switch, rotate engine 3 revolutions. Record compression pressure from third revolution. Continue test for remaining cylinders. See CYLINDER COMPRESSION PRESSURE SPECIFICATIONS  table for correct engine compression pressures.