Replacing Both Lambda Monitor Sensors

Replacing Both Oxygen Control Sensors

Read out fault memory, clear if necessary.





Remove microfilter.
Open cable duct on lower section of microfilter housing (2) and feed out cable(s).
Release screws (1) and remove lower section of microfilter housing (2).





Remove cover from injection valves.





Note:
^ The Lambda monitor sensors for cylinders 1 to 3 and 4 to 6 must not be mixed up at the plug connection to the wiring harness.
^ Mark plug connections.
^ Unclip the cable from the retainer. Disconnect connector. Unclip cable on rear side of engine from cable guide.





Release Lambda monitor sensor from cylinders 1 to 3 with special tool 11 7 030.
Release Lambda monitor sensor from cylinders 4 to 6 with special tool 11 7 020.

Installation:
The threads of new oxygen monitor sensors are already coated with Never Seize Compound.
If an oxygen monitor sensor is used again, apply a thin and even coat of Never Seize Compound (or equivalent) to the thread only.
Do not clean the oxygen monitor sensor section which protrudes into the exhaust line and ensure that it avoids all contact with lubricants.





Installation:
Secure Lambda monitor sensor for cylinders 1 to 3 with special tool 11 7 030.
Secure Lambda monitor sensor for cylinders 4 to 6 with special tool 11 7 020.
Tightening Torque, refer to Engine, Specifications, Mechanical.
Cover Lambda monitor sensors when applying underseal.
Pay attention to cable routing of Lambda monitor sensors.