Audi Workshop Service and Repair Manuals

Removing and installing front exhaust pipe with catalytic converter Removing   Note Vehicles with engine code BLY, BVZ, BHD, BMB comply with emission standard EU 2. On these vehicles some emissions-related components are not fitted, e.g. exhaust gas recirculation system, NOx sensor control unit -J583-, Lambda probe 2 -G108- and Lambda probe 2 after catalytic converter -G131-. Note this when working on the exhaust system.

–  Remove underbody cover (right-side) -arrows-. Engine code AXW, BLX:

–  Unplug electrical connector -1- from NOx sensor control unit -J583-. –  Detach NOx sensor control unit -J583--arrows- and move wiring with control unit clear. –  Unplug electrical connector -2- for exhaust gas temperature sender 1 -G235- and move wiring clear. –  Unplug electrical connector (black) -3- for Lambda probe after catalytic converter -G130- and move wiring clear. –  Unplug electrical connector (brown) -4- for Lambda probe 2 after catalytic converter -G131- and move wiring clear. Engine codes BLR, BLY, BVY, BVZ, BHD, BMB:

–  Unplug electrical connectors for Lambda probes. All vehicles (continued):

–  Remove front cross-piece for underbody -arrows-.   Note To avoid damage, the flexible joints in the front exhaust pipe must not be bent more than 10 °.

–  Separate exhaust system at clamp -arrows-.

–  Remove securing nuts -arrows- on front exhaust pipe/exhaust manifold.

–  Unbolt bracket for exhaust system -arrows-. –  Detach front exhaust pipe with catalytic converter. Installing Installation is carried out in the reverse order; note the following:   Note Renew gaskets and self-locking nuts. –  Align the exhaust system so it is free of stress → Chapter. Tightening torques

Component		Nm
Front exhaust pipe to exhaust manifold		25 1)2)
Drive shaft heat shield to cylinder block		35
Front tunnel cross-piece to body		23

l  1) Renew nuts/bolts l  2) Lubricate exhaust manifold studs with high-temperature paste. For high-temperature paste refer to → Parts catalogue.