Overview - Emissions Control System

WARNING: This page is about a different car, the 2023 Audi S3, 2023 Audi RS 3, 2023 Audi A3 Quattro, and 2023 Audi A3. However, it is still accessible from the selected car via links, so may be relevant.

Shown on a vehicle with AWD.

Courtesy of AUDI OF AMERICA, LLC

Bolt
- 20 Nm
Bracket
- There are different versions. Refer to the Parts Information for the allocation.
- Replace if damaged
Bolt
Tightening specification and sequence. Refer to Fig 3.
Catalytic Converter
- With front exhaust pipe
- There are different versions. Refer to the Parts Information for the allocation.
- Market-specific version: with particulate filter
- Protect from shocks and impact stress
- Removing and Installing. Refer to CATALYTIC CONVERTER, REMOVING AND INSTALLING .
- Exhaust System, Installing without Tension. Refer to EXHAUST SYSTEM, INSTALLING WITHOUT TENSION .
- After replacing the catalytic converter with the particulate filter an adaptation must be performed. Refer to PERFORM ADAPTATIONS AFTER COMPONENT REPLACEMENT .
Screw-Type Clamp
- Replace after removing
- Installation position. Refer to Fig 2.
- Tightening specification and sequence. Refer to Fig 3.
- 15 Nm
Seal
- Replace after removing
Turbocharger
- Removing and Installing. Refer to TURBOCHARGER, REMOVING AND INSTALLING .
Front Clamping Sleeve
- Before tightening, align the exhaust system without tension. Refer to EXHAUST SYSTEM, INSTALLING WITHOUT TENSION .
- Installation position. Refer to Fig 1.
- Tighten threaded connections evenly.
Nut
- 23 Nm

Installation position for front clamping sleeve

Fig 1: Installation Position For Front Clamping Sleeve

Courtesy of AUDI OF AMERICA, LLC

-- Install the clamping sleeve in the position shown.

Angle -α- = approximately 20°.
Threaded connection to the right.
The nuts are toward the top.

Installation position of the catalytic converter screw-type clamp

Fig 2: Installed Location of the Catalytic Converter Screw Clamp

Courtesy of AUDI OF AMERICA, LLC

Angle -α- = 30°.

Catalytic Converter - Tightening Specification and Sequence

Fig 3: Catalytic Converter - Tightening Specification and Sequence

Courtesy of AUDI OF AMERICA, LLC

-- Tighten the threaded connections in steps in the sequence shown:

Step	Screw-type clamp/bolt	Tightening Specification
1.	Screw-type clamp -1-	Position above the sealing flange, align (refer to Fig 2) and tighten with 5 Nm.
2.	Bolt -2-	Tighten with 2 Nm and immediately loosen by a 90° turn
3.	Screw-type clamp -1-	Tighten to 15 Nm.
4.	Bolt -2-	Tighten to 20 Nm