1.Before inspection, set the vehicle to the pre-inspection condition.
2.Disconnect the connector of the ignition coil, and then remove all of the ignition coils and spark plugs (Refer to GROUP 11D - Alternator and Ignition System ).

3.Disconnect all of the injector connectors.
  • Keep away from the spark plug hole when cranking.
  • If compression is measured with water, oil, fuel, etc., that has come from cracks inside the cylinder, these materials will become heated and will gush out from the spark plug hole, which is dangerous.
Cover the spark plug hole with a shop towel etc., and after the engine has been cranked, check that no foreign material is adhering to the shop towel.

5.Set compression gauge to one of the spark plug holes.
6.Crank the engine with the throttle valve fully open and measure the compression pressure.

    Standard value (at engine speed of 200 r/min): 1,180 kPa

    Limit (at engine speed of 200 r/min): Minimum 800 kPa
7.Measure the compression pressure for all the cylinders, and check that the pressure differences of the cylinders are below the limit.
Limit: Maximum 100 kPa
8.If there is a cylinder with compression or a compression difference that is outside the limit, pour a small amount of engine oil through the spark plug hole, and repeat the operations in steps from 5 to 7.
(1) If the compression increases after oil is added, the cause of the malfunction is a worn or damaged piston ring and/or cylinder inner surface.
(2) If the compression does not rise after oil is added, the cause is a burnt or defective valve seat, or pressure is leaking from the gasket.
9.Connect all of the injector connectors.
10.Install the spark plugs and ignition coils (Refer to GROUP 11D - Alternator and Ignition System ).
11.Turn the ignition switch to the "LOCK" (OFF) position and then connect the M.U.T.-III to the diagnosis connector (Refer to GROUP 00 - Precautions Before Service - M.U.T.-III Sub Assembly ).
12.Use the M.U.T.-III to erase the diagnosis codes.
note This will erase the diagnosis code resulting from the injector connectors being disconnected.