Compression Check: Testing and Inspection

Compression pressure, checking

Special tools, testers and auxiliary items
^ Compression tester US 112O

Test conditions

^ Engine oil temperature min. 30°C (86°F)

- Disconnect harness connector for engine speed (RPM) sensor G28.

- Disconnect ignition coil power output stage N157.

- Open throttle all the way (wide open throttle).

- Install compression tester US 1120.

Note:
Using the compression tester - Operating instructions.

- Operate starter until compression tester gauge shows no further pressure increase.

Compression pressure specifications
^ New: 10-13 bar (145-189 psi)
^ Wear limit: 7.5 bar (109 psi)
^ Permissible difference between all cylinders: 3 bar (44 psi)