Procedure steps

SAFETY INSTRUCTIONS: 

SPECIAL TOOLS AND TIGHTENING TORQUES: 

For additional information on special tools and tightening torques pertaining to this procedure, refer to the following:

• OVERVIEW OF TIGHTENING TORQUES 
• OVERVIEW SPECIAL TOOL 

PRE-PROCESSES: 

Prerequisite 

Switch off the ignition

1. Removing rear underbody protection 
   • Unscrew all bolts.
   • Remove underbody protection (1).
     Fig 1: Locating Underbody Protection Bolts

     Courtesy of BMW OF NORTH AMERICA, INC.
2. Release exhaust system from catalytic converter 
   NOTE: Description is for left component only. Procedure on the right side is identical.
   • Unscrew nuts (1).
     Fig 2: Identifying Exhaust System Nuts

     Courtesy of BMW OF NORTH AMERICA, INC.
   • Unscrew nuts (1).
   • Slacken nuts (2).
   • Lower exhaust system slightly at front.
     Fig 3: Identifying Exhaust System Bracket Nuts

     Courtesy of BMW OF NORTH AMERICA, INC.
3. Removing the acoustic cover 
   • Raise acoustic cover (1) and remove in direction of travel.
     Fig 4: Removing/Installing Acoustic Cover

     Courtesy of BMW OF NORTH AMERICA, INC.
4. Remove intake silencer housing on left and right 
   NOTE: Description is for left component only. Procedure on the right side is identical.
   • Unfasten clamp (1).
   • Disconnect connector (2) at the hot film air mass meter.
   • Loosen clamp (3).
   • Unclip oxygen sensor cable from intake silencer housing.
   • Detach the intake air filter housing from the intake port and pull off upwards.
     Fig 5: Removing Intake Silencer Housing

     Courtesy of BMW OF NORTH AMERICA, INC.
5. Remove right charge-air line 
   • Unfasten clamp (1).
   • Unfasten clamp (2).
   • Remove right charge air line (3).
     Fig 6: Identifying Right Charge Air Line And Clamp

     Courtesy of BMW OF NORTH AMERICA, INC.
6. Remove right clean air pipe 
   NOTE: Description is for left component only. Procedure on the right side is identical.
   • Pull off hoses (1) from clean air pipe.
   • Release screw (2).
   • Pull off clean air pipe (3) in direction of travel from turbocharger.
     Fig 7: Identifying Clean Air Pipe, Hoses And Screw

     Courtesy of BMW OF NORTH AMERICA, INC.
7. Remove left control sensor 
   • Unlock plug connection and disconnect.
   • Unclip control sensor cable at retaining clips.
   • Release control sensor using special tool 0 491 074 (11 7 020)  and a reversible ratchet (1).
     Fig 8: Removing/Installing Control Sensor Using Special Tool 11 7 020

     Courtesy of BMW OF NORTH AMERICA, INC.
8. Remove left monitoring sensor 
   • Release retaining clip (1).
   • Remove heat shield wire ring (2) over oxygen sensor.
   • Disconnect connector from oxygen sensor.
   • Detach oxygen sensor cable from retaining clips (3).
     Fig 9: Identifying Left Side Oxygen Sensor, Retaining Clip, Wire Ring

     Courtesy of BMW OF NORTH AMERICA, INC.
   • Release monitoring sensor (1) with special tool 0 491 074 (11 7 020)  .
     Fig 10: Removing/Installing Monitoring Sensor Using Special Tool 11 7 020

     Courtesy of BMW OF NORTH AMERICA, INC.
9. Remove right control sensor 
   • Unlock plug connection and detach.
   • Release control sensor cable from retaining clips.
   • Release control sensor with special tool 0 491 074 (11 7 020)  .
     Fig 11: Removing/Installing Control Sensor Using Special Tool 11 7 020

     Courtesy of BMW OF NORTH AMERICA, INC.
10. Remove right monitoring sensor 
    • Release retaining clip (1).
    • Remove heat shield wire ring (2) over oxygen sensor.
    • Disconnect connector from oxygen sensor.
    • Detach oxygen sensor cable from retaining clips (3).
      Fig 12: Identifying Right Side Oxygen Sensor, Retaining Clip, Wire Ring

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Release monitoring sensor (1) with special tool 0 491 074 (11 7 020)  .
      Fig 13: Removing/Installing Monitoring Sensor Using Special Tool 11 7 020

      Courtesy of BMW OF NORTH AMERICA, INC.
11. Remove upper heat shield 
    • Loosen screws (1).
    • Lift out holder.
      Fig 14: Identifying Upper Heat Shield Screws

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    • Release screw (1).
      Fig 15: Identifying Heat Shield Screw

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    • Release screw (1).
      Fig 16: Identifying Heat Shield Screw

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Loosen screws (1).
      Fig 17: Identifying Heat Shield Screw

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    • Loosen screws (1).
    • Lift out heat shield.
      Fig 18: Identifying Heat Shield Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
12. Remove heat shield at bottom 
    NOTE: For purposes of clarity: Illustration shows removed condition.
    • Release screw (1) from heat shield (2) and (3).
      Fig 19: Identifying Heat Shield Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Loosen screws (1) on left heat shield.
      Fig 20: Loosening Left Heat Shield Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Release screw (1) on right heat shield.
      Fig 21: Loosening Right Heat Shield Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Release screw (1) on heat shield at bottom right.
    • Unclip heat shield and remove.
      Fig 22: Releasing Heat Shield Screw

      Courtesy of BMW OF NORTH AMERICA, INC.
13. Remove holder for left monitoring sensor 
    • Loosen screws (1).
    • Remove holder for monitoring sensor (2).
      Fig 23: Identifying Monitoring Sensor Holder With Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
14. Remove catalytic converter for cylinders 5-8 
    • Release screw (1) on catalytic converter.
    • Release clamp (2) on catalytic converter.
      Fig 24: Identifying Catalytic Converter For Cylinders 5-8

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Loosen screws (1).
    • Pull crankcase ventilation (2) from cylinder head cover.
    • Loosen screws (3) on holder.
      Fig 25: Identifying Crankcase Ventilation And Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Loosen screws (1) for rear catalytic converter for cylinders 5-8 from cylinder head.
    • Remove catalytic converter for cylinders 5-8.
      Fig 26: Identifying Rear Catalytic Converter Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
15. Remove holder for right monitoring sensor 
    • Loosen screws (1).
    • Remove holder for monitoring sensor (2).
      Fig 27: Identifying Monitoring Sensor Holder And Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
16. Remove catalytic converter for cylinders 1-4 
    • Release screw (1) on catalytic converter.
    • Release clamp (2) on catalytic converter.
      Fig 28: Identifying Catalytic Converter For Cylinders 1-4

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Loosen screws (1).
    • Pull hose (2) from cylinder head cover.
    • Loosen screws (3) on holder.
      Fig 29: Identifying Hose And Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Loosen screws (1) on rear catalytic converter for cylinders 1-4 from cylinder head.
    • Remove catalytic converter for cylinders 1-4.
      Fig 30: Identifying Rear Catalytic Converter Screws

      Courtesy of BMW OF NORTH AMERICA, INC.

    Keyprocesses 

17. Remove vacuum pump 

    Prerequisite 

    Low pressure in brake servo must be removed. For that, press brake pedal several times.

    NOTE: Vacuum pump is fitted on cylinder head 1 to 4 at rear on intake camshaft.
    • Loosen screws (1).
    • Remove heat shield (2).
    • Remove vacuum hose.
      Fig 31: Identifying Heat Shield Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
    NOTE: Bolts (1) are secured against falling out.
    • Loosen screws (1).
    • Release screw (2).
    • Remove vacuum pump (3).
      Fig 32: Identifying Vacuum Pump Bolts And Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
18. Install vacuum pump 
    • Turn drive (1) in the right position before installation.
    • Renew sealing ring (2) and coat with grease to facilitate installation.
      Fig 33: Identifying Vacuum Pump Drive And Sealing Ring

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Align vacuum pump drive to groove (1) of intake camshaft.

    » Vacuum pump can best be installed when groove (1) is vertically aligned.

    Fig 34: Identifying Vacuum Pump Drive Groove Of Intake Camshaft

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Install vacuum pump (3).
    • Tighten screw (2).
    • Tighten screws (1).
      Fig 35: Identifying Vacuum Pump And Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
    • Mount heat shield (2).
    • Tighten screws (1).
    • Connect vacuum hose.
      Fig 36: Identifying Heat Shield Screws

      Courtesy of BMW OF NORTH AMERICA, INC.

    Postprocesses 

19. Install catalytic converter for cylinders 1-4 
    • Position catalytic converter for cylinders 1-4.
    • Tighten screws (1) on rear catalytic converter for cylinders 1-4 to cylinder head.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Catalytic converter to cylinder head
    M8	21 Nm

    Fig 37: Identifying Rear Catalytic Converter Screws For Cylinders 1-4

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten screws (3) on holder.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Holder of catalytic converter to cylinder head
    M8	21 Nm

    • Position hose (2) on cylinder head cover.
    • Tighten down screws (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Crankcase ventilation to cylinder head cover
    M6	10 Nm

    Fig 38: Identifying Cylinder Head Cover Hose And Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
    NOTE: Clamp (2) must be installed with screw pointing inwards. Otherwise, heat shield can no longer be installed on top.
    • Tighten new clamp (2) on catalytic converter.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Catalytic converter to turbocharger
    Replace clamp	13 Nm

    Fig 39: Identifying Catalytic Converter Clamp And Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten screw (1) on catalytic converter.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Holder of catalytic converter to catalytic converter
    M8	21 Nm

    » Ends of clamp must rest parallel to each other.

    Fig 40: Identifying V-Band Clamp Ends

    Courtesy of BMW OF NORTH AMERICA, INC.

    » If there is a gap between ends of clamp, bolted connection must be loosened and repeated.

    Fig 41: Locating Gap Between Ends Of Clamp

    Courtesy of BMW OF NORTH AMERICA, INC.

    » If ends of clamp are positioned beneath each other, bolted connection must be released and repeated.

    Fig 42: Locating V-Band Clamp End

    Courtesy of BMW OF NORTH AMERICA, INC.
20. Install holder for right monitoring sensor 
    • Position holder for monitoring sensor (2).
    • Tighten down screws (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Holder for monitoring sensor to cylinder head cover
    M6	10 Nm

    Fig 43: Identifying Monitoring Sensor Holder With Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
21. Install catalytic converter for cylinders 5-8 
    • Position catalytic converter for cylinders 5-8.
    • Tighten screws (1) on rear catalytic converter for cylinders 5-8 to cylinder head.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Catalytic converter to cylinder head
    M8	21 Nm

    Fig 44: Identifying Rear Catalytic Converter Screws For Cylinders 5-8

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten screws (3) on holder.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Holder of catalytic converter to cylinder head
    M8	21 Nm

    • Position crankcase ventilation (2) on cylinder head cover.
    • Tighten down screws (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Crankcase ventilation to cylinder head cover
    M6	10 Nm

    Fig 45: Identifying Crankcase Ventilation And Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
    NOTE: Clamp (2) must be installed with screw pointing inwards. Otherwise, heat shield can no longer be installed on top.
    • Tighten new clamp (2) on catalytic converter.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Catalytic converter to turbocharger
    Replace clamp	13 Nm

    Fig 46: Identifying Catalytic Converter Clamp And Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten screw (1) on catalytic converter.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Holder of catalytic converter to catalytic converter
    M8	21 Nm

    » Ends of clamp must rest parallel to each other.

    Fig 47: Identifying V-Band Clamp Ends

    Courtesy of BMW OF NORTH AMERICA, INC.

    » If there is a gap between ends of clamp, bolted connection must be released and repeated.

    Fig 48: Locating Gap Between Ends Of Clamp

    Courtesy of BMW OF NORTH AMERICA, INC.

    If ends of clamp are positioned beneath each other, bolted connection must be released and repeated.

    Fig 49: Locating Clamp Ends

    Courtesy of BMW OF NORTH AMERICA, INC.
22. Install holder for left monitoring sensor 
    • Position holder for monitoring sensor (2).
    • Tighten down screws (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Holder for monitoring sensor to cylinder head cover
    M6	10 Nm

    Fig 50: Identifying Monitoring Sensor Holder With Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
23. Install heat shield on the bottom 
    NOTE: For purposes of clarity: Illustration shows removed condition.
    • Position heat shield and clip it in.
    • Tighten screw (1) on heat shield at bottom right.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Heat shield to heat shield
    M6	10 Nm

    Fig 51: Installing Heat Shield On Bottom

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten screw (1) on right heat shield.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Heat shield to heat shield
    M6	10 Nm

    Fig 52: Loosening Right Heat Shield Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten screws (1) on left heat shield.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Heat shield to heat shield
    M6	10 Nm

    Fig 53: Installing Heat Shield

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten screw (1) from heat shield (2) and (3).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Heat shield to heat shield
    M6	10 Nm

    Fig 54: Identifying Heat Shield Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
24. Install heat shield, top 
    • Position heat shield.
    • Tighten down screws (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Heat shield to heat shield
    M6	10 Nm

    Fig 55: Identifying Heat Shield Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten down screws (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Heat shield to heat shield
    M6	10 Nm

    Fig 56: Identifying Heat Shield Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten screw (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Heat shield to heat shield
    M6	10 Nm

    Fig 57: Identifying Heat Shield Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten screw (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Heat shield to heat shield
    M6	10 Nm

    Fig 58: Identifying Heat Shield Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Position holder.
    • Tighten down screws (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Holder for acoustic cover to cylinder head cover
    M6	10 Nm

    Fig 59: Identifying Acoustic Cover Screws

    Courtesy of BMW OF NORTH AMERICA, INC.
25. Install right monitoring sensor 
    NOTE: Risk of damage! Part of oxygen sensor that projects into exhaust branch (sensor ceramics) must not be cleaned or coated with lubricant.
    • Coat thread of control sensor thinly and evenly with NEVER-SEEZ compound.
    • Tighten monitoring sensor (1) with special tool 0 491 074 (11 7 020)  .
      Fig 60: Removing/Installing Monitoring Sensor Using Special Tool 11 7 020

      Courtesy of BMW OF NORTH AMERICA, INC.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Monitoring sensor to engine
    M18 x 1, 5	50 Nm

    • Position heat shield wire ring (2) over oxygen sensor.
    • Lock retaining clip (1).
    • Connect connector of oxygen sensor.
    NOTE: Risk of damage! Make sure cables are routed correctly and without abrasion.
    • Lock oxygen sensor cable in retaining clips (3).
      Fig 61: Identifying Right Side Oxygen Sensor, Retaining Clip, Wire Ring

      Courtesy of BMW OF NORTH AMERICA, INC.
26. Install right control sensor 
    NOTE: Risk of damage! Part of oxygen sensor that projects into exhaust branch (sensor ceramics) must not be cleaned or coated with lubricant.
    • Coat thread of control sensor thinly and evenly with NEVER-SEEZ compound.
    • Tighten control sensor using special tool 0 491 074 (11 7 020)  and a torque wrench (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Control sensor to engine
    M18 x 1, 5	50 Nm

    Fig 62: Removing/Installing Control Sensor Using Special Tool 11 7 020

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Connect connector of control sensor.
    NOTE: Risk of damage! Make sure cables are routed correctly and without abrasion.
    • Lock control sensor cable in retaining clips.
27. Install left monitoring sensor 
    NOTE: Risk of damage! Part of oxygen sensor that projects into exhaust branch (sensor ceramics) must not be cleaned or coated with lubricant.
    • Coat thread of monitoring sensor thinly and evenly with NEVER-SEEZ compound.
    • Tighten monitoring sensor (1) with special tool 0 491 074 (11 7 020)  .
    TIGHTENING TORQUES SPECIFICATION
    
    

    Monitoring sensor to engine
    M18 x 1, 5	50 Nm

    Fig 63: Removing/Installing Monitoring Sensor Using Special Tool 11 7 020

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Position heat shield wire ring (2) over monitoring sensor.
    • Lock retaining clip (1).
    • Connect connector of monitoring sensor.
    NOTE: Risk of damage! Make sure cables are routed correctly and without abrasion.
    • Lock monitoring sensor cable in retaining clips (3).
      Fig 64: Identifying Left Side Oxygen Sensor, Retaining Clip, Wire Ring

      Courtesy of BMW OF NORTH AMERICA, INC.
28. Install left control sensor 
    NOTE: Risk of damage! Part of oxygen sensor that projects into exhaust branch (sensor ceramics) must not be cleaned or coated with lubricant.
    • Coat thread of control sensor thinly and evenly with NEVER-SEEZ compound.
    • Tighten control sensor using special tool 0 491 074 (11 7 020)  and a torque wrench (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Control sensor to engine
    M18 x 1, 5	50 Nm

    Fig 65: Removing/Installing Control Sensor Using Special Tool 11 7 020

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Connect connector of control sensor.
    NOTE: Risk of damage! Make sure cables are routed correctly and without abrasion.
    • Lock control sensor cable in retaining clips.
29. Install right clean air pipe 
    NOTE: Description is for left component only. Procedure on the right side is identical.
    • Connect clean air pipe (3) to exhaust turbocharger.
    • Tighten screw (2).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Clean air pipe to exhaust turbocharger
    M6	10 Nm

    • Connect hoses (1) of clean air pipe.
      Fig 66: Identifying Clean Air Pipe, Hoses And Screw

      Courtesy of BMW OF NORTH AMERICA, INC.
30. Install right charge air line 
    • Check gasket on exhaust turbocharger and renew if necessary.
    • Install right charge air line (3).
    • Tighten clamp (2).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Charge air line to charge air cooler
    Replace clamp	3.5 Nm

    • Tighten clamp (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Charge air line to exhaust turbocharger
    Replace clamp	3, 5 Nm

    Fig 67: Identifying Right Charge Air Line And Clamp

    Courtesy of BMW OF NORTH AMERICA, INC.
31. Install left and right intake silencer housing 
    NOTE: Description is for left component only. Procedure on the right side is identical.
    • Connect intake silencer housing on intake port.
    • Clip oxygen sensor cable in on intake silencer housing.
    • Install clamp (3).
    • Connect connector (2) at the hot film air mass meter.
    • Tighten clamp (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Clamp to air duct

    3 Nm

    Fig 68: Identifying Connector And Clamps

    Courtesy of BMW OF NORTH AMERICA, INC.
32. Install acoustic cover 
    NOTE: Ensure correct fit!
    • Insert acoustic cover (1) into existing rubber guides.
      Fig 69: Identifying Acoustic Cover

      Courtesy of BMW OF NORTH AMERICA, INC.
33. Renew gasket for catalytic converter 1-4 and catalytic converter 5-8 
    NOTE: Description is for left component only. Procedure on the right side is identical.
    • Clean sealing surfaces.
    • Replace gasket (1).
      Fig 70: Identifying Catalytic Converter Gasket

      Courtesy of BMW OF NORTH AMERICA, INC.
34. Connect exhaust system to catalytic converter 
    NOTE: Description is for left component only. Procedure on the right side is identical.
    • Position exhaust system on catalytic converter.
    • Tighten down nuts (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Exhaust system to catalytic converter
    M8	20 Nm
    Replace nuts

    Fig 71: Identifying Exhaust System To Catalytic Converter Nuts

    Courtesy of BMW OF NORTH AMERICA, INC.
    • Tighten down nuts (2).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Holder of exhaust system to exhaust system
    M8	22 Nm

    • Tighten down nuts (1).
    TIGHTENING TORQUES SPECIFICATION
    
    

    Holder of exhaust system to transmission
    M8	22 Nm

    Fig 72: Identifying Exhaust System Bracket Nuts

    Courtesy of BMW OF NORTH AMERICA, INC.
35. Installing underbody protection at rear 
    NOTE: Ensure correct fit!
    • Position underbody protection (1).
    • Tighten down all screws.
      Fig 73: Locating Underbody Protection Screws

      Courtesy of BMW OF NORTH AMERICA, INC.
    TIGHTENING TORQUES SPECIFICATION
    
    

    Rear underbody protection to body
    Screw	3 Nm
    Nut	2.5 Nm

36. Check function of DME. 
37. Check vacuum pump for leaks and correct operation.