Genuine 2007 BMW 335i Knock Sensor

2007 BMW 335i Knock Sensor Parts Questions & Experts Answers

• Q:

  How to remove and reinstall a turbo engine knock sensor on 2007 BMW 335i?

  Posted by Samuel R.

  A:

  Turbo engine knock sensors are under the intake manifold on the left side of the cylinder head. Disconnect negative(-) battery cable and cover battery terminal to keep cable from accidentally contacting terminal. With engine fully cooled, remove intake manifold. Disconnect electrical connectors, remove and seal fuel line connections. Be prepared to catch dripping fuel. When working with high pressure fuel lines observe clean working habits. Any dirt or debris introduced into system will cause malfunctions. Disconnect knock sensor electrical connector on left side of engine block. Remove knock sensor mounting bolts on side of cylinder block. Remove sensors. Note the installed angle of the knock sensor on the block before removing it. Reinstall the sensor in the same position. Be sure to use a torque wrench when tightening the sensor mounting bolt. Clean knock sensor contact surface on engine block and sensor before installing knock sensor. Do not overtighten knock sensors. Installation is reverse of removal. Remember to replace knock sensor mounting bolt, be sure sensor harness is rerouted as before, check for fuel system leaks, and clear fault codes from ECM memory.

  Answered by BMW Parts Specialist Chaz / Oct 14, 2022