Removing and installing/replace catalytic converter for cylinders 1-3 (S55 engine)

Only perform this repair work on an engine that has cooled down.

Necessary preliminary work: 

• Remove OXYGEN SENSOR , cylinders 1-3
• Remove MONITORING SENSOR , cylinders 1-3
• Remove STIFFENING PLATE .
• Remove EXHAUST SYSTEM .

Removal: 

Release screw (1).

Remove the clamp (2).

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Remove seals (1).

Unfasten screws (2).

Remove the flange plate (3).

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Secure the catalytic converter to prevent falling.

Release nut (2) on holder.

Loosen the screws (1) and remove the anti-roll bar link (3).

Remove the catalytic converter toward the bottom.

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Preparation for installation: 

Replace the gasket (1) on the exhaust turbocharger.

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Installation: 

Install the catalytic converter.

Install the anti-roll bar link (3).

Tighten down screws (1).

Twin-clutch gearbox  tightening torque 28 00 1AZ .

Manual transmission  tightening torque 23 00 1AZ Tighten the nut (2) on the holder.

Tightening torque 18 31 1AZ .

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Install the flange plate (3).

Parts: Replace the gaskets and screws.

Tighten down screws (2).

Install the gaskets (1).

Tightening torque 18 31 1AZ .

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Parts  : Replace the screw and clamp.

Install the clamp (2).

Tighten screw (1).

Tightening torque 18 31 2AZ .

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Required follow-up work: 

• Install the OXYGEN SENSOR for cylinder 1-3
• Install the MONITORING SENSOR for cylinder 1-3
• Install the STIFFENING PLATE .
• Install EXHAUST SYSTEM .
• Check exhaust system for leaks