Front Oxygen Sensor

Front Oxygen Sensor, B235E/R

To Remove

Important:
^ The cables must not be twisted. Twisted cables exposed to vibration can break.
^ The oxygen sensor is sensitive to impact and jolting and must be handled with care.






1. Remove the engine cover.
2. Remove the oxygen sensor connector from the holder by pressing the lugs together as shown in the illustration.






3. Remove the bypass pipe and heat shield.
4. Uncut the cable tie to the oxygen sensor and draw out the cables.
5. Remove the oxygen sensor from the turbo outlet pipe.

To Fit

Important: The oxygen sensor is sensitive to impact and jolting and must be handled with care. It is important that the connections between the oxygen sensor and nipple are gas-tight.

1. Coat the oxygen sensor threads with Molycote 1000 (30 20 971) to prevent binding.






2. Fit the oxygen sensor.
Tightening torque 55 Nm (41 ft. lbs.)

Important: Chemicals such as contact spray and grease must not come into contact with the oxygen sensor connectors.






3. Draw out the cable and plug in the connector.
4. Fasten the cable to the water pipe with a cable tie.
5. Fit the heat shield and bypass pipe.
6. Fit the upper engine cover.