BMW 13627568421 Knock Sensor

The knock sensors for the 6-cylinder engines are mounted beneath the intake manifold gasket, on the left bank of the cylinder head. Electrical connection should be disconnected by unscrewing the negative terminal, while battery terminal should be protected against accidental touching by placing a terminal cap on it. Before eradicating the battery it is worthwhile to know the precautions associated with battery removal. Upon complete cooling of the engine, one should take out the intake manifold. Secondly, unscrew the knock sensor electrical harness connector on the lateral side of the engine. Lose the knock sensor mounting bolts at the side of the cylinder block, and pull out the sensors. The position of the knock sensor to the block has to be noted before its removal; to ensure that it will be reinstated in the identical position, the knock sensor mounting bolt has to be tightened with a torque wrench. The other knock sensor should then be cleaned on the contact surface on the engine block and on the sensor before the new knock sensor is fitted and tightened without over- tightening. All in all, there are four things that should be checked: to look for fault codes and, if necessary, to start the procedure of ECM memory reset.