Knock Sensor: Service and Repair

- Switch off ignition.
- Remove upper section of manifold.





- Disconnect plug connector (1) on camshaft sensor.
- Disconnect plug connection (2) on impulse sensor.





- Unfasten screw connection (1) for cable channel in lower section of manifold.





- Disconnect plug connection (2) on the sensors and remove from bracket (1).





Location:
- On cylinder bank 1-2, the knock sensor (1) can be seen the oil filter and intake manifold.





- The knock sensor for cylinder bank 1-2 can be accessed from above between the intake pipes for cylinders 2 and 3. To gain access, intake hose 8 for the fuel injection valves on neck (1) of fuel rail must be removed.





NOTE: The knock sensor (1) on cylinder bank 1-2 is screw mounted to water pipe on engine block. Unfasten screw (1) on knock sensor.

Tightening Torque = 13 Nm.





- Unfasten screw (1) on water pipe.





- Screw (1) of water pipe (2) is slightly loosened. Pull water pipe (2) gently forwards and remove knock sensor (3) from behind water pipe.





- Knock sensor (2) on cylinder bank 3-4: unfasten screw and remove complete knock sensor.

Tightening Torque = 13 Nm.

Installation Note: Interrogate fault memory of DME-control unit, check faults in memory then cancel fault memory.