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. Disconnect injector harness connectors.
3. Disconnect CCV tube and breather drain tube from valve cover.
4. Remove the cylinder head cover. Refer to COVER(S), Cylinder Head, Removal, 6.7L .
5. Disconnect harness from injectors.
6. Remove the cylinder head cover carrier gasket. Refer to COVER(S), Cylinder Head, Removal, 6.7L .
7. Bring the cylinder to be tested to TDC.
8. Remove the high pressure fuel line between the cylinder head and the fuel rail for the cylinder to be tested.
9. Install Fuel Rail Cap (special tool #9864, Cap, Fuel Rail) onto the rail.
10. Remove the high pressure connector nut and high pressure connector with High Pressure Connector Remover (special tool #9015, Remover, High Pressure Connector).
11. Remove the exhaust and intake rocker lever.
12. Use Fuel Injector Remover\Installer (special tool #9010A, Remover/Installer, Fuel Injector) to remove the injector and copper sealing washer.
13. Install Compression Test Adapter (special tool #9007, Adapter, Compression Test) into the injector bore.
14. Connect the leakage tester and perform the leakage test procedure on each cylinder according to the tester manufacturer's instructions.
15. Upon completion of the test check and erase any engine related fault codes.