Necessary preliminary work

• Remove ACOUSTIC COVER
• REMOVE BOTH INTAKE SILENCER HOUSINGS .
• Remove EXHAUST SYSTEM  .
• Remove both control sensors. See REPLACING LEFT CONTROL SENSOR (N63) and REPLACING RIGHT CONTROL SENSOR (N63) .
• Remove both monitoring sensors. See REPLACING LEFT MONITOR SENSOR (N63) and REPLACING RIGHT MONITOR SENSOR (N63) .

Picture shows the left side, carry out the operation for the right side in an identical way.

Release screws (1).

Remove cable clips on left and right.

Fig 1: Identifying Screws And Cable Clips On Left And Right

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Remove rubber mounts (1) and release screws underneath.

Tightening torque 13 71 5AZ .

Remove cable clip (2).

Remove the HEAT SHIELD (3) at top.

Fig 2: Identifying Rubber Mounts, Cable Clip And Heat Shield At Top

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Remove heat shield (1) at rear left and right.

This is described further below in the instructions.

Release screw (2) on catalytic converter.

Tightening torque 18 32 4AZ .

Release clamp (3) on catalytic converter.

Replace clamp (3).

Tightening torque 18 32 1AZ .

Installation note: 

The clamp (3) must be installed with the screw toward the inside (illustration). Otherwise, the heat shield can no longer be installed on top.

Fig 3: Identifying Heat Shield At Rear Left And Right, Clamp With Screw On Catalytic Converter

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Installation note: 

The ends of the V-band clamps must rest parallel to each other.

Tightening torque 18 32 1AZ .

Fig 4: Identifying V-Band Clamps

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Installation note: 

If you can see a gap between the ends of the V - band clamps, release and then repeat the screw connection.

Tightening torque 18 32 1AZ .

Fig 5: Locating V - Band Clamps Gap

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Installation note: 

If the ends of the V-band clamps are positioned under each other, release and then repeat the screw connection.

Tightening torque 18 32 1AZ .

Fig 6: Locating V - Band Clamps Position

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Release screw (1) from heat shields (2) and (3).

Screw (1) is located between the catalytic converters.

Fig 7: Identifying Screws On Heat Shields And Catalytic Converter

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Release screws (1) on left heat shield.

Unclip left heat shield and remove.

Fig 8: Removing Screws Of Left Heat Shield

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Release screw (1) on right heat shield.

Fig 9: Identifying Screw Of Right Heat Shield

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Release screw (1) on heat shield at bottom right.

Unclip heat shield and remove.

Fig 10: Identifying Screw Of Heat Shield At Bottom Right

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Release screws (1).

Detach hose (2) from cylinder head cover.

Release screws (3) on holder.

Tightening torque 18 32 2AZ .

Fig 11: Identifying Hose Of Cylinder Head Cover And Screws On Holder

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Release screws (1) on catalytic converter, cylinders 5 - 8, rear, at cylinder head.

Tightening torque 18 32 3AZ .

Remove catalytic converter for cylinders 5-8.

Fig 12: Identifying Screws On Catalytic Converter

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Installation note: 

Picture shows the engine removed.

Replace gasket (1) on left exhaust turbocharger.

Fig 13: Identifying Gasket On Left Exhaust Turbocharger

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Installation note: 

Clean sealing surfaces.

Replace gasket (1).

Fig 14: Identifying Gasket

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Assemble engine.

Check exhaust system for leak tightness.