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Compression Check: Testing and Inspection



11 00 039 Checking compression of all cylinders (N12, N14)







- Read out fault memory of DME control unit
- Check stored faults
- Rectify faults
- Clear fault memory







IMPORTANT:
High tension - mortal danger.
Interrupt power supply to ignition coils.
Read and comply with notes on compression pressure check.







Necessary preliminary tasks:
- Remove spark plugs.







Unscrew tip (1) from special tool 11 0 222.

IMPORTANT: Then check the Schrader valve that is now visible for secure seating.







Prepare special tool 11 0 222 in conjunction with 11 8 732 and 11 8 731.







Screw special tool 11 0 222 onto special tool 11 8 731 to 10 Nm.







IMPORTANT: Do not forget to oil spark plug thread of special tool 11 8 731.

Screw special tool 11 0 222 by hand into spark plug thread and connect special tool 11 0 224.
Use adapter lead (1) if the compression pressure is being checked with the BMW diagnosis system.
Depress accelerator pedal and actuate starter until compression pressure stops rising.
- Nominal values, compression pressure







Assemble engine
Now clear the fault memory.