Removing oxygen sensor

CAUTION: Oxygen sensor can be damaged if handled improperly.

Do not remove the plastic cap on the thread until just prior to fitting the oxygen sensor. The thread grease must under no circumstances come into contact with the plug.
Protect sensors - before and after fitting -against mechanical shocks.
Sensors that were dropped on the floor must not be used owing to the risk of a broken ceramic insulator.
The cables must not be twisted or kinked when the sensors are screwed in. Avoid puffing on the cable and plug.
Cleanliness in the housing of the plug connections is of utmost importance for the function of the oxygen sensor. Particles of dirt can impair the function of the oxygen sensor. Therefore, the plug must be protected against any and all types of soiling.
Sensors with soiled or damaged plug must no longer be used.
Protect the cables and plugs when transporting the exhaust system with the sensors already fitted.
High-pressure cleaning equipment must not be used in the area of the sensors and plug connections.
Contact and corrosion agents, e.g. Stabilant, must not be applied on the plug contacts of the oxygen sensors.

Disconnect plug connection behind the catalytic converter, cylinder bank 4-6.

Fig 1: Disconnecting Plug Connection Behind Catalytic Converter
Courtesy of PORSCHE OF NORTH AMERICA, INC.
Disconnect the plug connection in front of catalytic converter on rear-axle support, cylinder bank 4-6

Fig 2: Disconnecting Plug Connection In Front Of Catalytic Converter On Rear-Axle
Courtesy of PORSCHE OF NORTH AMERICA, INC.
Undo oxygen sensor using the specified ring wrench (wrench size 22 mm).

Fig 3: Removing Oxygen Sensor

Courtesy of PORSCHE OF NORTH AMERICA, INC.