Engine Compression Inspection

NOTE: After this inspection, you must reset the engine control module (ECM)/powertrain control module (PCM), otherwise the ECM/PCM will continue to stop the fuel injectors from functioning.
  1. Warm up the engine to normal operating temperature (cooling fan comes on).
  1. Turn the ignition switch to LOCK (0).
  1. Turn the ignition switch to ON (II).
  1. Select PGM-FI, INSPECTION, then ALL INJECTORS STOP on the HDS.
  1. Turn the ignition switch to LOCK (0).
  1. Remove the four spark plugs.
  1. Attach a compression gauge to a spark plug hole.
  1. Open the throttle fully, crank the engine with the starter motor and measure the compression.
    Compression Pressure:
    Above 880 kPa (9.0 kgf/cm 2 , 128 psi)

  1. Measure the compression on the remaining cylinders.
    Maximum Variation:
    Within 200 kPa (2.0 kgf/cm 2 , 28 psi)

  1. If the compression is not within specifications, check the following items, then remeasure the compression.
    • Damaged or worn valves and seats
    • Damaged cylinder head gasket
    • Damaged or worn piston rings
    • Damaged or worn piston and cylinder bore
  1. Remove the compression gauge from the spark plug hole.
  1. Install the four spark plugs.
  1. Select ECM/PCM reset to cancel the ALL INJECTORS STOP on the HDS.