Removing Oxygen Sensor Upstream Of Catalytic Converter

→ Let hot components cool down.

→ Wear personal protective gear.

→ Do not remove the plastic cap on the thread until just prior to fitting.

→ Protect oxygen sensors from impact of any kind.

→ Do not kink or twist the cables when screwing in the sensors.

→ Do not re-use dirty or damaged components.

1. Observe instructions when working with oxygen sensors.

   → 2400AW PRECAUTIONARY MEASURES WHEN HANDLING OXYGEN SENSORS .

   Installation position of oxygen sensors on side 1-3 

   Fig 1: Identifying Oxygen Sensors On Side 1-3

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
   1. Oxygen sensor downstream of catalytic converter - black cable
   2. Oxygen sensor upstream of catalytic converter - blue cable
   3. Cable holder
   4. M6 fastening screw → Tightening torque: 10 Nm (7.5 ft. lb.) 
   5. Cable mounting points for oxygen sensor downstream of catalytic converter
   6. Cable mounting points for oxygen sensor upstream of catalytic converter

   Oxygen sensors on side 4-6

   Fig 2: Identifying Oxygen Sensors On Side 4-6

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
   1. Oxygen sensor downstream of catalytic converter - black cable
   2. Oxygen sensor upstream of catalytic converter - blue cable
   3. Cable holder
   4. M6 fastening screw → Tightening torque: 10 Nm (7.5 ft. lb.) 
   5. Cable mounting point for oxygen sensor downstream of catalytic converter
   6. Cable mounting points for oxygen sensor upstream of catalytic converter
2. Unclip cable for oxygen sensor upstream of catalytic converter (blue) at the mounting points (item 6)  .
3. Loosen and unscrew oxygen sensor -1-  .
   1. 3.1. Tool recommendation: Torque wrench with open-jawed wrench insert Nr.95 -2-. 
      Fig 3: Loosening Oxygen Sensor Using Tool

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.