Legacy Outback Limited AWD F4-2.5L DOHC (1998)
Compression Check: Testing and Inspection
1) After warming-up the engine, turn ignition switch to OFF.
2) Make sure that the battery is fully charged.
3) Remove all the spark plugs.
4) Disconnect connectors from fuel injectors.
5) Fully open throttle valve.
6) Check the starter motor for satisfactory performance and operation.
7) Hold the compression gauge tight against the spark plug hole.
CAUTION: When using a screw-in type compression gauge, the screw (put into cylinder head spark plug hole) should be less than 18 mm (0.71
in) long.
8) Crank the engine by means of the starter motor, and read the maximum value on the gauge when the pointer is steady.
9) Perform at least two measurements per cylinder, and make sure that the values are correct.
Compression (350 rpm and fully open throttle):
Standard: 1,216 kPa (176 psi)
Limit: 941 kPa (137 psi)
Difference between cylinders: 49 kPa (7 psi), or less
