Exhaust System: Service and Repair

Exhaust system components, removing and installing

Notes:
^ After working on the exhaust system make sure that the system is not under stress, and that it has sufficient clearance from the bodywork. If necessary, loosen double and single clamps and align silencer and exhaust pipe so that sufficient clearance is maintained to the bodywork and the support rings are evenly loaded.
^ Replace self-locking nuts.
^ Components marked with * will be checked by On Board Diagnostic (OBD):





1-Tunnel bridge
2-Mount
^ Note installation position see Fig. 4
3-25 Nm
4-Front exhaust pipe with three way catalytic converterCatalytic Converter
5-40 Nm
^ Replace
6-Gasket
^ Replace
7-TurbochargerTurbocharger
8-Heated Oxygen Sensor (HO2S) (G39)*, 50 Nm
^ Grease only the threads with "G 052 112 A3"; "G 052 112 A3" must not get into the slots on the probe body
^ Remove and install with oxygen sensor open ring spanner set 3337
^ If sealing ring is leaking nip open and replace.
^ Checking.
9-Connector
^ For Heated Oxygen Sensor (H02S) (G39) and oxygen sensor heater (Z19)
Vehicles with engine code AWD:
^ Black, 4 pin
Vehicles with engine code AWP, AWW:
^ Black, 6-pin
^ Contacts gold plated
10-Oxygen-Sensor (02S) behind Three Way Catalytic Converter (TWC) (G130)*, 50 Nm
^ Grease only the threads with "G 052 112 A3"; "G 052 112A3" must not get into the slots on the probe body
^ Remove and install with oxygen sensor open ring spanner set 3337
^ If sealing ring is leaking nip open and replace.
^ Checking.
11-Connector
^ For Oxygen Sensor (02S) behind Three Way Catalytic Converter (TWC) (G130) and oxygen sensor heating (Z29)
^ Black, 4 pin
^ Contacts 3 and 4 goldplated
12-Double clamp
^ Note installed position see Fig. 3
13-40 Nm
14-Mount
15-Center and rear silencer
^ As standard, center and rear silencers are installed as a single component. In cases of repair the center and rear silencer are supplied individually and with a double clamp for connecting.
^ Separating point: see Fig. 1
^ Aligning rear silencer free of stress see Fig. 2
16-Mount





Fig. 1 Separating point on exhaust pipe
^ Separate exhaust pipe at right angles at separating point-arrow 2-.
^ When installing position repair double clamp-4-between points-arrows 1 and 3-. Tightening torque: 40 Nm





Fig. 2 Aligning rear silencer free of stress
^ The mounting pins on exhaust pipe must run parallel with tunnel bridge (dimension-x-on left and right the same).





Fig. 3 Installed position of double clamp
^ Position double clamp approx. 5 mm away from mark -A- arrow 1-.

Note: Mark -A- is valid for vehicles with manual and automatic transmissions.





Fig. 4 Installation position of mount
^ Angled side on foot of mount-arrow-points forwards.