18 32 050 Removing and installing/replace catalytic converter for cylinders 1-3 (N54, N54T)

Special tools required:

WARNING: Risk of burning!
This repair work may only be carried out on an exhaust system which has cooled down.

Necessary preliminary tasks:

Remove underbody protection . See 51 47 491 REMOVING AND INSTALLING/REPLACING REAR UNDERBODY PROTECTION or 51 47 490 REMOVING AND INSTALLING / REPLACING FRONT UNDERBODY PROTECTION
Remove EXHAUST SYSTEM .
Remove cable clip on side of transmission for control sensor/monitoring sensor.
All-wheel drive vehicles only:
Remove right bearing support.

NOTE: The oxygen sensors are in danger of being damaged when the exhaust manifolds are removed and installed.

Remove monitoring sensor from cylinders 1 to 3.

Remove control sensor, cylinders 1 to 3.

Unscrew nuts.

Tightening torque 18 20 2AZ .

Fig 1: Locating Cylinders Nuts

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Release screws.

Remove holder (1).

Fig 2: Locating Cylinders Holder Nuts

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Unfasten clamp. In so doing, secure catalytic converter (1) against falling out.

Feed out catalytic converter (1) towards bottom and remove.

Installation note:

Clean sealing surface. Replace seal and clamp.

Tightening torque 18 31 3AZ .

Fig 3: Locating Catalytic Converter

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Installation note:

Secure installation position of catalytic converter with special tool 18 0 110 .

Fig 4: Identifying Special Tool (18 0 110)

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Reassemble the vehicle.

Check exhaust system for leaks.