Removing and installing parts of secondary air system — VW
Removing and installing parts of secondary air system on VW: factory workshop procedure for engines AEH, AGN, AGU, AJH.
Workshop procedure for VW — the factory write-up, straight from real workshop data.
📐 20 workshop diagrams for AEH
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.
Removing and installing parts of secondary air system
Note
Components marked with an * are checked by self-diagnosis:
Rep. Gr. 01; Fault memory; Reading and erasing engine control unit fault memory
.
Components marked with ** are checked by final control diagnosis:
Rep. Gr. 01; Final control diagnosis; Performing final control diagnosis
.
Secondary air pump relay
J299
**
Fig.
1
Intake manifold
2
Vacuum actuator
For intake manifold change-over.
3
To intake manifold.
4
To fuel pressure regulator.
5
O-ring
Renew if damaged.
6
Combination valve
Check
Chapter
.
7
Gasket
Renew.
8
Air duct
In cylinder head
9
10 Nm
10
Connection
For combination valve and coolant hose
Coolant hose schematic diagram
Chapter
.
11
5 Nm
12
Pressure hose
Check for secure seating.
Press together at front to release.
13
Connection
14
Bracket
For secondary air pump motor.
Attached to sump and cylinder block
15
20 Nm
16
Connector
Black, 2-pin
For secondary air pump motor.
17
Rubber bush
18
Secondary air pump motor
V101
**
Check
Chapter
.
19
Air filter
Clean if soiled.
20
Retaining clamp
21
Intake hose
Check for secure seating.
Press together at front to release.
22
Connector
Black, 2-pin
Before pulling off, mark allocation of connector to component
23
Non-return valve
Note installation position.
White connection faces to
secondary air inlet valve
N112
/
variable intake manifold changeover valve
N156
24
Intake manifold changeover valve
N156
*/**
The valve will be activated from the engine control unit (pulsed).
25
Secondary air inlet valve
N112
*/**
The valve will be activated from the engine control unit (pulsed).
26
Vacuum reservoir
Clipped in bracket
Item
and secured with bolt
27
13 Nm
28
Bracket
For vacuum reservoir, intake manifold changeover valve and secondary air inlet valve
Relay for secondary air pump
J299
** - relay position 22 -
Relay is located on lower multifunctional unit relay holder.
Note
If tools are necessary to pull relays or control units out of the relay plate, first disconnect battery earth strap
Before disconnecting battery earth strap obtain code for radios with anti-theft coding.
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.
Ask about my car →Other VW procedures
- Checking catalyst
- Checking Lambda probe and Lambda regulation – VW 1.6 AEH/AKL
- Testing injection quantity, leak tightness and spray pattern of injectors
- Adaptation of throttle valve control unit
- Removing and installing throttle cable – Audi A3
- Removing engine · 41 torque figures
- Removing and installing camshaft – VW Golf Cabriolet · 47 torque figures
- Adjusting valve timing – VW Passat B5 · 83 torque figures
- Removing and installing camshafts – VW Passat B6 · 39 torque figures
- Removing and installing coolant pump · 53 torque figures
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.