18 32 050 Removing and installing/replacing catalytic converter (N55)

WARNING: This page does not describe the selected car, but rather 21 other vehicles, including the 2017 BMW 550i GT xDrive, 2017 BMW 535i GT xDrive, 2017 BMW 535i GT, 2016 BMW 550i GT xDrive, and 2016 BMW 535i GT xDrive. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Risk of burning!
Only perform this repair work after the exhaust system has cooled down.

Necessary preliminary work:

Remove front UNDERBODY PROTECTION .
Remove rear UNDERBODY PROTECTION .
Remove EXHAUST SYSTEM .

NOTE: The oxygen sensors are in danger of being damaged when the catalytic converters are removed and installed.
Remove CONTROL SENSOR , cylinders 1 to 3.
Remove MONITORING SENSOR from cylinders 1 to 3.

Release nuts (1) and (2).

Tightening torque 18 20 1AZ .

Fig 1: Identifying Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

Release clamp (1). The clamp must be renewed every time it is removed.

Tightening torque 18 31 2AZ .

In so doing, secure catalytic converter against falling out.

Feed out catalytic converter and remove.

Installation note:

Clean sealing surface. Renew clamp and seal.

Fig 2: Identifying Clamp

Courtesy of BMW OF NORTH AMERICA, INC.

Reassemble the vehicle.

Check exhaust system for leaks.