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Home >> Volkswagen >> 2004 >> Passat GLS 4Motion, 4D Sedan, Standard >> Repair and Diagnosis >> Engine Performance >> System >> 1.8L - Engine Exhaust System - AUG, AWM >> Exhaust System, Emission Control >> Exhaust system components, assembly overview >> Notes
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Exhaust system components, assembly overview: Notes

NOTE: The following list refers to items in Fig 1.
  1. 30 Nm 
    • Always replace
    • Coat threads with G 052 112 A3
  2. Exhaust manifold 
  3. Gasket 
    • Always replace
  4. Heated Oxygen Sensor (HO2S) - G39- before catalytic converter, 50 Nm 
    • Grease only threads with G 052 112 A3 hot bolt paste (anti-seize compound). Grease must not get into slots on sensor
    • Use 3337 to remove and install
    • Checking:

    See HEATED OXYGEN SENSOR (HO2S) AND OXYGEN SENSOR CONTROL BEHIND THREE WAY CATALYTIC CONVERTER (TWC), CHECKING

  5. Three Way Catalytic Converter (TWC) 
  6. Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- 
    • Grease only threads with G 052 112 A3 hot bolt paste (anti-seize compound). Grease must not get into slots on sensor
    • Use 3337 to remove and install
    • Checking:

    See HEATED OXYGEN SENSOR (HO2S) AND OXYGEN SENSOR CONTROL BEHIND THREE WAY CATALYTIC CONVERTER (TWC), CHECKING

  7. 25 Nm 
    • Always replace
    • Coat threads with G 052 112 A3
  8. Marking 
    • 3x at perimeter
    • Slide double clamp item - 21 - up to marking on tube
  9. Support ring 
    • With retainer ring
  10. Support ring 
  11. 25 Nm 
  12. Rear muffler 
    • At factory, center and rear mufflers are installed as a single component. Replacement center and rear mufflers are supplied separately, with double clamp for connecting joint.
    • Removing and installing:
    • Using VAG 1523 Chassis saw, cut at right angle through connecting pipe at separation point - 18 -.
  13. Dimension -a- = approx. 7 to 9 mm 
    • Exhaust system must be cold
    • Arrow shows direction of travel
    • To adjust exhaust system, slide double clamp - 21 - onto exhaust pipe up to marking - 8 - and tighten slightly Slide center and rear mufflers far enough forward that dimension -a- is obtained. Tighten double clamp.
  14. Bolt head must face fuel tank 
  15. Angle -a- =30+/- 5 
  16. Bolt end must not be below double clamp 
    • Double clamp viewed in direction of travel
  17. Angle -B- = 10 + 5° 
  18. Separating point 
    • Approx. 160 to 180 mm in front of rear muffler, marked by recess in pipe.
  19. Double clamp 
    • Tighten evenly to 40 Nm
  20. Center muffler 
  21. Double clamp 
    • Tighten evenly to 40 Nm
  22. Decoupling element 
    • max. flex 10°.
  23. Support ring 
  24. Front exhaust pipe 
  25. 30 Nm 
    • Always replace
    • Coat threads with G 052 112 A3
  26. Washer 
    CAUTION: Part numbers are for reference only. Always check with your Parts Dept. for the latest parts information.
Fig 1: Identifying Exhaust System Components
G03480345Courtesy of VOLKSWAGEN OF AMERICA, INC.