Checking the engine: Notes

• Ignition off
• Disconnect system relay 2/14
• Remove spark plugs.

  Check the compression at wide open throttle (WOT).

  In particular, check for uneven compression between the cylinders.

  NOTE: Compression testing should always be carried out at wide open throttle (WOT) and with the engine at operating temperature. Diagnostic trouble codes (DTCs) ECM-24 and ECM-A3 will be stored because the system relay is disconnected.
  Fig 2: Identifying Engine Compartment Integrated Relay/Fusebox

  Courtesy of VOLVO CARS OF NORTH AMERICA.

Is the compression OK? 

• YES 

  FAULT NOT FOUND:  Troubleshooting has been completed.

• NO 

  Refer to Engine repairs