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 .
All-wheel drive vehicles only :
Remove REINFORCEMENT PLATE .

NOTE: When removing and installing the catalytic converter there is the risk of damaging the control 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 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 And V-Band Clamp Separation Point

Courtesy of BMW OF NORTH AMERICA, INC.

Release nuts (1).

Tightening torque 18 20 1AZ .

Unfasten screws (2).

Tightening torque 18 20 2AZ .

Remove holder (3) for catalytic converter.

Unscrew nuts (4).

Tightening torque 18 20 1AZ .

Rubber mount of catalytic converter.

Feed out catalytic converter (5) and remove.

Fig 3: Identifying Catalytic Converter Holder, Screws And Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

Reassemble the vehicle.

Check exhaust system for leaks.