Removal & Installation

WARNING: This page is about a different car, the 2005 BMW 530i, 2005 BMW 525i, 2004 BMW 530i, and 2004 BMW 525i. However, it is still accessible from the selected car via links, so may be relevant.

Necessary preliminary tasks:

Read out fault memory of DME control unit
Switch off ignition

WARNING: Scalding hazard!

Only perform this task on an engine that has cooled down.

Unclip plug connection (1) and disconnect.

Release both oxygen sensors (2) with special tool 11 7 020.

Fig 1: Releasing Both Oxygen Sensors

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

Threads of new oxygen sensors are already coated with Never Seez compound.

If an oxygen sensor is reused, only apply a thin and uniform coat of Never Seez compound to thread.

Oxygen sensor section projecting into exhaust system must not be cleaned or come into contact with lubricant.

Pay attention to cable routing for oxygen sensors.

Use special tool 11 7 020 to tighten down oxygen sensor.

Tightening torque, see 11 78 1AZ in ENGINE - TIGHTENING TORQUES .

Cover oxygen sensors when applying underseal.

Installation:

Check stored fault messages.

Now clear the fault memory.