Compression Check: Testing and Inspection

Test compression pressure at normal operating temperature. If minimum compression pressure is below specification, test cylinder for leaks. Testing and Inspection

Unscrew all spark plugs for testing.

Pull off plug connection (X27) at wiring harness and plug adapter cable (01) with 1-pin coupling into plug connection (terminal 50) of wiring harness

Crank engine with the starter. Connect the specified terminals for this step.

On vehicles with bolted terminal blocks, use the crocodile clamp with the 1-pin connector in place of the adapter cable.





Separate the cable connector (terminal 16, arrow), switch off ignition to prevent ignition coil and fuel pump being operated.





Connect the terminals identified with arrows.


Testing




1 Unscrew all spark plugs.
2 Crank engine several times to expel residues and soot (selector lever in position N or P).
3 Push compression pressure recorder into spark plug hole of the respective cylinder.
4 For testing, crank engine about 8 revolutions with throttle valve open.

Test all the cylinders in this way. Move test sheet into the relevant position in compression pressure recorder before testing each cylinder.