Exhaust System Overview

Fig 1: Identifying Exhaust System Assembly Overview, Engine Codes AXX, BPY, BWA

Courtesy of AUDI OF AMERICA, LLC

1. Nut
   • Replace
   • 40 Nm
   • Coat turbocharger stud bolts with hot bolt paste.
2. Front Exhaust Pipe with Catalytic Converters and Front Muffler
   • With front exhaust pipe
   • Protect from shocks and impact stress
   • With flex joint
   • Flex joint must not be bent more than 10° - otherwise it may be damaged
   • Removing and installing, refer to FRONT EXHAUST PIPE WITH CATALYTIC CONVERTERS AND FRONT MUFFLER 
   • Install exhaust system free of stress, refer to EXHAUST SYSTEM, ALIGNING 
3. Oxygen Sensor (O2S) after Three Way Catalytic Converter (TWC) -G130- and Heater for Oxygen Sensor 1 after Catalytic Converter -Z29-
   • Tightening specification, 55 Nm
   • Only use hot bolt paste to grease thread; do not let paste get onto slits of oxygen sensor body
   • Removing and installing, refer to Removal and Installation
4. Retaining Loop
   • Replace if damaged
5. Nut
   • 23 Nm
6. Retaining Loop
   • Replace if damaged
7. Rear Muffler
   • Original equipment as one unit with center muffler. For repairs, replace each separately.
   • Separating point CENTER AND REAR MUFFLERS, SEPARATING 
   • Install exhaust system free of stress, refer to EXHAUST SYSTEM, ALIGNING 
8. Suspended Mount
   • Replace if damaged
9. Bolt
   • 23 Nm
10. Rear Clamping Sleeve
    • For individual replacement of center and rear mufflers
    • Installed location, refer to Fig 3
    • Tighten bolts evenly
11. Center Muffler
    • Original equipment as one unit with rear muffler. For repairs, replace each part separately.
    • Separating point CENTER AND REAR MUFFLERS, SEPARATING 
    • Install exhaust system free of stress, refer to EXHAUST SYSTEM, ALIGNING 
12. Retaining Loop
    • Replace if damaged
13. Bolt
    • 23 Nm
14. Front Clamping Sleeve
    • Before tightening, ensure exhaust system is tension-free, refer to EXHAUST SYSTEM, ALIGNING 
    • Installed location, refer to Fig 2
    • Tighten bolts evenly
15. Nut
    • 23 Nm
16. Suspended Mount
17. Bolt
    • 23 Nm
18. Suspended Mount
19. Support
20. Bolts
    • 40 Nm
21. Gasket
    • Replace
22. Heated Oxygen Sensor (HO2S) -G39- and Oxygen Sensor (O2S) Heater -Z19-
    • Tightening specification, 55 Nm
    • Only use hot bolt paste to grease thread; do not let paste get onto slits of oxygen sensor body
    • Removing and installing, refer to Removal and Installation

Fig 2: Clamping Sleeve Location

Courtesy of AUDI OF AMERICA, LLC

-- Install clamping sleeve so that the end of the bolt does not extend beyond the lower edge of the clamping sleeve.

• Threaded connection points toward the right.

Fig 3: Clamping Sleeve Location

Courtesy of AUDI OF AMERICA, LLC

-- Install clamping sleeve so that the end of the bolt does not extend beyond the lower edge of the clamping sleeve.

• Threaded connection points to the rear.