Compression Check: Testing and Inspection

1GR-FE ENGINE MECHANICAL: ENGINE: ON-VEHICLE INSPECTION

ON-VEHICLE INSPECTION

1. INSPECT COMPRESSION
(a) Warm up and stop the engine.
(b) Remove the circuit opening relay.
(c) Remove the V-bank cover.
(d) Remove the air cleaner assembly.
(e) Remove the ignition coils.
(f) Remove the spark plugs.





(g) Inspect the cylinder compression pressure.
(1) Insert a compression gage into the spark plug hole.
SST: 09992-00500
(2) Fully open the throttle.
(3) While cranking the engine, measure the compression pressure.
Compression pressure:
1,300 kPa (13.3 kgf/cm2, 189 psi)
Minimum pressure:
1,000 kPa (10.2 kgf/cm2, 145 psi)
Difference between each cylinder:
100 kPa (1.0 kgf/cm2, 15 psi)

NOTE:
- Use a fully-charged battery so the engine speed can be increased to 250 rpm or more.
- Inspect the other cylinders in the same way.
- Measure the compression in as short a time as possible.
(4) If the cylinder compression is low, pour a small amount of engine oil into the cylinder through the spark plug hole and repeat steps (1) through (3) for cylinders with low compression.

- If adding oil increases the compression, the piston rings and/or cylinder bore may be worn or damaged.

- If pressure stays low, a valve may be stuck or seated improperly, or there may be leakage from the gasket.