Catalytic Converter: Service and Repair

2004 Volkswagen Jetta Sedan (9M2) L4-2.0L (AVH)SECTION Service and Repair


Exhaust Manifold, Front Exhaust Pipe With Three Way Catalytic Converter (TWC) And Attachments (Vehicles With Engine Code AVH, AZG)







1 Combination valve
2 10 Nm
3 25 Nm
4 25 Nm
5 Heated Oxygen Sensor (HO2S) -G39- bank 1*, 50 Nm
- Component location: in front catalytic converter
- Only use "G 052 112 A3" to grease thread; do not let "G 052 112 A3" get onto slit of oxygen sensor
- Voltage supply of oxygen sensor heater via Fuel Pump (FP) Relay -J17-
6 Connector
- Black, 6-pin
- Terminals are gold-plated
- For Heated Oxygen Sensor (HO2S) 1 before Three Way Catalytic Converter (TWC) -G39- and Oxygen Sensor (O2S) heater -Z19-
- Component location: At right vehicle underside
7 30 Nm
8 Connection tube
9 Connecting piece, 35 Nm
10 25 Nm
11 Suspended mount
12 Connector
- Brown, 4-pin
- Terminals 3 and 4 gold-plated
- For Heated Oxygen Sensor (HO2S) 2 behind Three Way Catalytic Converter (TWC) -G130- and Oxygen Sensor (O2S) Heater 1 (behind Three Way Catalytic Converter (TWC)) -Z29-
- Component location: At right vehicle underside
13 Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- bank 1*, 50 Nm
- Component location: In rear catalytic converter
- Only use "G 052 112 A3" to grease thread; do not let "G 052 112 A3" get onto slit of oxygen sensor
- Voltage supply of oxygen sensor heater via Fuel Pump (FP) Relay -J17-
14 to front muffler
15 Front exhaust pipe with Three Way Catalytic Converter (TWC)
- Check catalytic converter
16 40 Nm
17 Seal
18 Exhaust manifold
19 Seal
20 Heat shield.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.