Cylinder Leak Down Test

DIAGNOSIS AND TESTING - CYLINDER COMPRESSION/LEAKAGE TESTS

CYLINDER COMBUSTION PRESSURE LEAKAGE
The combustion pressure leakage test provides an accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
^ Exhaust and intake valve leaks (improper seating).
^ Leaks between adjacent cylinders or into water jacket.
^ Any causes for combustion/compression pressure loss

1. Start and operate the engine until it attains normal operating temperature.
2. FOR EARLY BUILDS Remove the breather cover and cylinder head cover.
3. FOR EARLY BUILDS Disconnect all three injector wire harness connectors at the rocker housing.
4. FOR LATE BUILDS Disconnect injector harness connectors.
5. FOR LATE BUILDS Disconnect breather tube and breather drain tube from valve cover.
6. FOR LATE BUILDS Remove the cylinder head cover.
7. FOR LATE BUILDS Disconnect harness from injectors.
8. FOR LATE BUILDS Remove the cylinder head cover carrier gasket.
9. Bring the cylinder to be tested to TDC.
10. Remove the high pressure fuel line between the cylinder head and the fuel rail for the cylinder to be tested.
11. Install capping Tool 9011 onto the rail.
12. Remove the high pressure connector nut and high pressure connector with Tool 9015.
13. Remove the exhaust and intake rocker lever.
14. Use Tool 9010 to remove the injector and copper sealing washer.
15. Install compression test Tool 9007 into the injector bore.
16. Connect the leakage tester and perform the leakage test procedure on each cylinder according to the tester manufacturer's instructions.
17. Upon completion of the test check and erase any engine related fault codes.