Removing and Installing Lambda Sensors Upstream of Catalytic Converter

Removing And Installing Lambda Sensors Upstream Of Catalytic Converter

Tools







Technical Values







Preliminary work

WARNING:
Objects or loads falling down
- Risk of squashing or crushing
- Secure components to prevent them from falling down.

1. Remove right or left rear wheel.
2. Remove rear wall cover.
3. Remove engine compartment lid.

Removing lambda sensor upstream of catalytic converter

CAUTION:
Hot components
- Risk of burns
- Let hot components cool down.
- Wear personal protective gear.

NOTE:
Incorrect handling of oxygen sensors
- Risk of damage to oxygen sensors
- Different exhaust emission behaviour
- 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. Open plug connection for lambda sensor (blue cable).










1.1. Unclip cable plug and connecting cable from the holder. For cylinder bank 1-3, see illustration -1-, for cylinder bank 4-6, see illustration -1-.
1.2. Release and disconnect cable plug.

2. Expose connecting cable on the cylinder head as far as the lambda sensor upstream of the catalytic converter.
2.1. Take photographs of the line routing using a digital camera if necessary.
2.2. Cut tie-wraps on the line if necessary.







3. Remove lambda sensor upstream of catalytic converter -arrow-.
3.1. Make sure that the connecting cable can also turn when removing the lambda sensor.

Installing lambda sensor upstream of catalytic converter
1. Visually check the sealing ring -arrow- and thread on the lambda sensor for damage.







1.1. Replace lambda sensor if damaged.

2. Fit lambda sensor.
2.1. Grease thread of lambda sensor with a light coating of Optimol Paste MF (000.043.207.07) before refitting. New lambda sensors are pre-greased for installation.







2.2. Fit and screw in lambda sensor by hand. - Lambda sensor upstream of catalytic converter
2.3. Make sure that the connecting cable can also turn when installing the lambda sensor.
2.4. Tighten lambda sensor using accessory for torque wrench: angled open-end/ring wrench Nr.96-3. - Tightening torque: 50 Nm (37 ft. lbs.) ± 8 Nm ( ± 6 ft. lbs.)

3. Route blue connecting cable as far as the lambda sensor and clip it into the holders. Replace tie-wraps if necessary.
4. Fit plug connection for lambda sensor.










4.1. Clip cable plug and connecting cable into the holder. For cylinder bank 1-3, see illustration -1-, for cylinder bank 4-6, see illustration -1-.
4.2. Connect and lock cable plug.

Subsequent work
1. Install right or left rear wheel.
2. Install rear wall cover.
3. Install engine compartment lid.
4. Read out the fault memory and correct any faults that are present, then erase the fault memory.