Exhaust manifold, front exhaust pipe and catalytic converter with attachments — VW
Exhaust manifold, front exhaust pipe and catalytic converter with attachments on VW: factory workshop procedure for engines ALT, AQN, AVU, AYD.
Workshop procedure for VW — the factory write-up, straight from real workshop data.
📐 54 workshop diagrams for ALT
Real factory drawings for this job — timing marks, bolt locations and routing. Locked in the free view.
📋 Procedure
ℹ️ Torque figures below come verbatim from workshop data — always cross-check against your vehicle's factory manual before final tightening.
Exhaust manifold, front exhaust pipe and catalytic converter with attachments
Note
Components marked with an
*
are checked by self-diagnosis:
Fault memory
Rep. gr.
01
Reading and erasing fault memory
.
Renew self-locking nuts.
25 Nm
Renew.
Washer
Heat shield
Lambda probe
G39
*
50 Nm
Remove and install with
Lambda probe open ring spanner set
3337
.
Grease only the threads with
G 052 112 A3
;
G 052 112 A3
must not get into the slots on the probe body.
If seal is leaking, nip open and renew.
If renewed, erase learnt values and adapt engine control unit anew:
Engine control unit
Rep. gr.
24
Erasing learnt values of control unit for engine electronics
.
Checking Lambda control:
Checking functions
Rep. gr.
24
Checking Lambda probe and Lambda control before catalytic converter
.
Connector
Black, 6-pin.
For
Lambda probe
G39
and
Lambda probe heating
Z19
.
Secured on left of bulkhead below expansion tank (looking forwards).
Exhaust manifold
With cut-out for secondary air system.
Gasket
Renew.
Catalytic converter
To remove, remove air filter and pressure pipe for secondary air system.
If renewed, erase learnt values and adapt engine control unit anew:
Engine control unit
Rep. gr.
24
Erasing learnt values of control unit for engine electronics
.
Checking catalytic converter
Chapter
Connector
Brown, 4-pin.
For
Lambda probe after catalytic converter
G130
and
Lambda probe heating 1 after catalytic converter
Z29
.
Secured on left of bulkhead below expansion tank (looking forwards).
Lambda probe after catalytic converter
G130
*
50 Nm
Remove and install with
Lambda probe open ring spanner set
3337
.
Grease only the threads with
G 052 112 A3
;
G 052 112 A3
must not get into the slots on the probe body.
If seal is leaking, nip open and renew.
If renewed, erase learnt values and adapt engine control unit anew:
Engine control unit
Rep. gr.
24
Erasing learnt values of control unit for engine electronics
.
Checking Lambda control:
Checking functions
Rep. gr.
24
Checking Lambda probe and Lambda control after catalytic converter
.
40 Nm
Renew.
Coach bolt
To centre silencer
Double clamp
Slide double clamp onto front exhaust pipe up to stop.
40 Nm
Front exhaust pipe
Mounting
Individual components for vehicles with a manual gearbox
Fig.
.
Individual components for vehicles with an automatic gearbox
Fig.
.
25 Nm
Renew.
Individual components of mountings (vehicles with manual gearbox)
1
Buffer
2
Spacer sleeve
3
Washer
4
Right plate
5
Washer
6
Hexagon bolt
7
Spacer sleeve
8
Left plate
9
Spring
10
Hexagon bolt
11
Self-locking nut, 25 Nm
Individual components of mountings (vehicles with automatic gearbox)
1
Washer
2
Bracket with buffer
3
Spacer sleeve
4
Front exhaust pipe
5
Hexagon bolt, 25 Nm
6
Hexagon bolt
7
Spring
8
Self-locking nut, 25 Nm
TorqFix answers live for your specific car — tell it the engine code and it serves the matching sequence, torque figures and wiring for that exact variant.
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Who makes these pages, and how
TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.
The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.
Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com
The story behind TorqFix →Workshop data on this page last updated 20 Sep 2026.