18 32 050 Removing and installing/replacing catalytic converter (N20)

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

Necessary preliminary tasks:

Remove front UNDERBODY PROTECTION .
Remove rear UNDERBODY PROTECTION .
Remove EXHAUST SYSTEM .
Four-wheel drive vehicles only:
Remove STIFFENING PLATE

NOTE: When removing and installing the catalytic converter there is the risk of damage to the control sensor and monitoring sensor.

REMOVE THE CONTROL SENSOR .

REMOVE MONITORING SENSOR .

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

Tightening torque 18 31 2AZ .

Installation note:

Clean sealing surface. Renew clamp and seal.

Fig 1: Identifying Catalytic Converter Clamp

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note:

When installing the catalytic converter make sure that the separation point (1) of the V-band clamp is aligned with the center of the welding spot (2) on the catalytic converter.

This guarantees that the wastegate valve lever does not collide with the V-band clamp.

Fig 2: Identifying Welding Spot On Catalytic Converter

Courtesy of BMW OF NORTH AMERICA, INC.

Release nuts (1).

Tightening torque 18 20 1AZ .

Pull off rubber mounts from the catalytic converter.

Unfasten screws (2).

Tightening torque 18 20 2AZ .

Unscrew nuts (3).

Tightening torque 18 20 1AZ .

Remove holder for catalytic converter.

Pull out catalytic converter towards the bottom and remove.

Fig 3: Identifying Catalytic Converter, Nut And Screws

Courtesy of BMW OF NORTH AMERICA, INC.

Reassemble the vehicle.

Check exhaust system for leaks.