247319 Removing and installing lambda sensors downstream of catalytic converter

WM 247319 Removing and installing lambda sensors downstream 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. -> 44051900 Removing and installing wheel - section on "Removing" Removal and Replacement.
2. Remove rear wall cover. -> 555919 Removing and installing rear wall cover - section on "Removing" Service and Repair.
3. Remove engine compartment lid. -> 557819 Removing and installing engine compartment lid - section on "Removing" 557819 Removing and Installing Engine Compartment Lid.

Removing lambda sensor downstream of catalytic converter

CAUTION

Hot components

- Risk of burns

-> Let hot components cool down.
-> Wear personal protective gear.

NOTICE

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 (black cable).
1.1. Unclip cable plug -1- and connecting cable -2- from the holder on the rear-axle carrier.





Connector for lambda sensor downstream of catalytic converter

1.2. Release and disconnect cable plug.
2. Expose connecting cable on the cylinder head as far as the lambda sensor downstream of the catalytic converter.
2.1. Take photographs of the line routing using a digital camera if necessary.
3. Remove lambda sensor downstream of catalytic converter -arrow-.





Lambda sensor downstream of catalytic converter

3.1. Make sure that the connecting cable can also turn when removing the lambda sensor.

Installing lambda sensor downstream 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.





Lambda sensor thread

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





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 ftlb.)+/-8 Nm (+/-6 ftlb.)
3. Route black connecting cable as far as the lambda sensor and clip it into the holders. Replace tie-wraps if necessary.
4. Connect and lock cable plug -1-.





Connector for lambda sensor downstream of catalytic converter

4.1. Clip cable plug -1- and connecting cable -2- into the holder.

Subsequent work

1. Install right or left rear wheel. -> 44051900 Removing and installing wheel - section on "Installing" Removal and Replacement.
2. Install rear wall cover. -> 555919 Removing and installing rear wall cover - section on "Installing" Service and Repair.
3. Install engine compartment lid. -> 557819 Removing and installing engine compartment lid - section on "Installing" 557819 Removing and Installing Engine Compartment Lid.
4. Read out the fault memory and correct any faults that are present, then erase the fault memory. -> 033500 On-board diagnosis - section on "Reading out" 033500 On-board diagnosis (OBD).