Cylinder Compression Pressure
- Run engine until operating temperature is reached.
- Remove engine cover. Remove cover from over ignition coils.
- Mark each ignition coil and remove. Remove spark plugs. Remove system relay from relay box located behind driver-side strut tower. See Figure.
- Separate engine speed (RPM) sensor electrical connector. RPM sensor is located on flywheel side of engine. See Fig 1.
- Install compression tester into spark plug hole of cylinder No. 1. Switch ignition to ON position. Hold throttle at Wide Open Throttle (WOT) position. Switch ignition to START position and crank engine over until compression gauge reads maximum cylinder pressure. Switch ignition to OFF position. Read compression values. Compression should be 160-189 psi (1100-1300 kPa). Maximum compression difference between cylinders is 29 psi (200 kPa). If values are not as specified, diagnose and repair as necessary. If values are OK, go to next step.
- Repeat procedure in step 5 for all cylinders. Go to next step.
- Install components when compression check is complete. Tighten spark plugs to 18 ft. lbs. (25 N.m). Tighten ignition coils to 89 INCH lbs. (10 N.m). Install ignition coil cover and engine cover and tighten fasteners to 72 INCH lbs. (8 N.m).
- Start engine and check for proper function. Retrieve and diagnose DTCs using scan tool.
Courtesy of VOLVO CARS OF NORTH AMERICA, INC.