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Knock Sensor: Service and Repair



Replacing Knock Sensor (M52TU, M54, M56)

Necessary preliminary tasks:
- Check stored fault messages.
- Switch off ignition.
- Remove intake air manifold.







Unclip plug connection (1) from holder of cable duct (2) and disconnect.







Release screw (1) and remove knock sensor for cylinder bank 1-3.







Release screw (2) and remove knock sensor for cylinder bank 4-6.







Installation:
Clean support face of knock sensors on engine block.

Tightening torque,
2AZ Knock Sensor 20 Nm

Installation:
Read out fault memory of control unit of Digital Motor Electronics (DME).
Now clear the fault memory.