[11A] ENGINE MECHANICAL <4G6-SOHC> - - ON-VEHICLE SERVICE - COMPRESSION PRESSURE CHECK | PRINT PAGE / INDEX / PRIOR / NEXT

| COMPRESSION PRESSURE CHECK
| Before inspection, set the vehicle to the pre-inspection condition. Disconnect the spark plug cables. Remove all of the spark plugs. Disconnect the crank angle sensor connector. NOTE: Doing this will prevent the engine-A/T-ECU from carrying out ignition and fuel injection. CAUTION 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.
| Set compression gauge to one of the spark plug holes. Crank the engine with the throttle valve fully open and measure the compression pressure. Standard value (at engine speed of 250 r/min): 1,320 kPa <4G63> 1,270kPa <4G64> Limit (at engine speed of 250 r/min): Minimum 930 <4G63> Minimum 880 <4G64> Measure the compression pressure for all the cylinders, and check that the pressure differences of the cylinders are below the limit. Limit: Maximum 98 kPa 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 (6) to (8). 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. If the compression dose not rise after oil is added, the cause is a burnt or defective valve seat, or pressure is leaking from the gasket. Connect the crank angle sensor connector. Install the spark plugs and spark plug cables. Use the MUT-II/III to erase the diagnosis codes. NOTE: This will erase the diagnosis code resulting from the crank angle sensor connector being disconnected.

[11A] ENGINE MECHANICAL <4G6-SOHC> - - ON-VEHICLE SERVICE - COMPRESSION PRESSURE CHECK | PRINT PAGE / INDEX / PRIOR / NEXT

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