12 14 600 Removing/replacing knock sensors (N52, N52K, N51)

WARNING: This page does not describe the selected car, but rather 14 other vehicles, including the 2013 BMW 328xi, 2013 BMW 328i, 2012 BMW 328xi, 2012 BMW 328i, and 2011 BMW 328xi. However, it is still accessible from the selected car via links, so may be relevant.

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 .

The end faces of aluminium screws/bolts are painted blue for the purposes of reliable identification.

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
Switch off ignition
Disconnect Battery Negative Lead
Remove Intake Air Manifold

Unlock plug (1) and remove.

Fig 1: Identifying Plug

Courtesy of BMW OF NORTH AMERICA, INC.

Release screws on both knock sensors (1) and remove knock sensors (1).

Installation:

Replace aluminium screws.

For tightening torque refer to 1AZ in 12 14 ELECTRONIC SHIFT UNITS OR CONTROL UNITS .

Fig 2: Identifying Knock Sensors And Screws

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

Clean support face of knock sensors on engine block.

Fig 3: Identifying Knock Sensors Support Face

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Check stored fault messages.

Now clear the fault memory.