Highlander 4WD V6-3.3L (3MZ-FE) (2004)
Compression Check: Testing and Inspection
9. INSPECT COMPRESSION
a. Warm up and stop the engine.
b. Disconnect the injector connectors.
c. Remove the intake air surge tank.
d. Remove the 6 ignition coils.
e. Remove the 6 spark plugs.
f.
Check the cylinder compression pressure.
SST 09992-00500
1. Insert a compression gauge into the spark plug hole.
2. Fully open the throttle.
3. While cranking the engine, measure the compression pressure.
Compression pressure: 1.5 MPa (15.3 kgf/cm2, 218 psi)
Minimum pressure: 1.0 MPa (10.2 kgf/cm2, 145 psi)
Difference between each cylinder: 100 kPa (1.0 kgf/cm2, 15 psi)
NOTICE:
^
Always use a fully charged battery to obtain engine speed of 250 rpm or more.
^
Check other cylinder's compression pressure in the same way.
^
This measurement must be done as quickly 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 inspect again.
HINT:
^
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 in the gasket.