Crankshaft Position Sensor: Service and Repair

2011 BMW 128i Convertible (E88) L6-3.0L (N51)SECTION Service and Repair


12 14 521 Replacing Crankshaft Pulse Generator (N52, N52K, N51, N53)







IMPORTANT: Read and comply with notes on protection against electrostatic discharge (ESD protection).







IMPORTANT:
Aluminium magnesium materials.

No steel screws/bolts may be used due to the threat of electrochemical corrosion.

A magnesium crankcase requires aluminium screws/bolts exclusively.

Aluminium screws/bolts must be replaced each time they are released.

Aluminium screws/bolts are permitted with and without colour coding (blue).

For reliable identification:

Aluminium screws/bolts are not magnetic.

Jointing torque and angle of rotation must be observed without fail (risk of damage).







Necessary preliminary tasks:
- Read out fault memory of DME control unit
- Turn off ignition

NOTE: Installation location of pulse generator for crankshaft is underneath starter motor.

Preparatory tasks:
- Remove intake plenum







Detach plug (1) from crankshaft pulse generator (2).

Release screw.

Installation:
Replace aluminium screws.

Tightening torque 12 14 2AZ.

Withdraw pulse generator (2) from crankcase.

Installation:
Replace sealing ring.







NOTE:
Check stored fault messages.
Delete fault memory.





RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.