246919 Removing and installing oxygen sensors ahead of catalytic converter on DFI engines

WM 246919 Removing and installing oxygen sensors ahead of catalytic converter on DFI engines

Technical values









Preliminary work
Cylinder bank 1 to 4
1. Remove air-cleaner element -> 242419 Removing and installing air-cleaner element on DFI engines - section on "Removing" Service and Repair and make sure the oxygen sensor cable is accessible.
2. Remove heat protection panel on the generator. -arrows at front- The heat protection panel remains fitted on the exhaust manifold.





Heat protection panels on V8 naturally aspirated engine

3. Remove primary catalytic converter. -> 267619 Removing and installing primary catalytic converter on V8 4.8-litre DFI engines - section on "Removing" 267619 Removing and installing primary catalytic converter on 4.8-litre V8 DFI enginesCylinder bank 5 to 8
1. Remove air-cleaner element -> 242419 Removing and installing air-cleaner element on DFI engines - section on "Removing" Service and Repair and make sure the oxygen sensor cable is accessible.
2. Remove underbody panelling under the engine. -> 108019 Removing and installing engine guard (underbody panel) on DFI engines - section on "Removing" 108019 Removing and installing engine guard (underbody panelling)

Removing oxygen sensors ahead of catalytic converter

Cylinder bank 1 to 4
CAUTION

The oxygen sensor cable can be damaged if twisted.

- Change in emissions.
- Check Engine light comes on.

-> Always expose oxygen sensor cable so that the wire can turn when unscrewing or screwing in the sensor.
-> Do not kink cable.

1. Disconnect cable plug on oxygen sensor and release cable around the exhaust manifold and generator. => Oxygen sensor on naturally aspirated engine M48/01, cylinders 1 to 4





Oxygen sensor on naturally aspirated engine M48/01, cylinders 1 to 4









Exhaust manifold on naturally aspirated engine M48/01, cylinders 1 to 4





2. Carefully unscrew oxygen sensor at the exhaust manifold. -1- Use a short open-ended wrench if necessary and tap loose with a hammer.





Oxygen sensor in exhaust manifold (cylinder bank 1 to 4)
Cylinder bank 5 to 8
CAUTION

The oxygen sensor cable can be damaged if twisted.

- Change in emissions.
- Check Engine light comes on.

-> Always expose oxygen sensor cable so that the wire can turn when unscrewing or screwing in the sensor.
-> Do not kink cable.

1. Disconnect cable plug on oxygen sensor and release cable around the exhaust manifold. => Oxygen sensor on naturally aspirated engine M48/01, cylinders 5 to 8





Oxygen sensor on naturally aspirated engine M48/01, cylinders 5 to 8









Exhaust manifold on naturally aspirated engine M48/01, cylinders 5 to 8





5. Remove oxygen sensor from below at the exhaust manifold using a suitable tool. -1-





View of oxygen sensor in exhaust manifold from below (cylinder bank 5 to 8)

Installing oxygen sensors ahead of catalytic converter

Cylinder bank 1 to 4
1. Carefully coat the thread of the oxygen sensor with 000.043.207.07.
2. Carefully screw in oxygen sensor at the exhaust manifold by hand. -1- Screw on oxygen sensor correctly. Difficult to access with torque wrench. Careful tightening by hand is acceptable.=> Tightening torque: 45 Nm (33 ftlb.)+/-5 Nm (+/-3.5 ftlb.)





Oxygen sensor in exhaust manifold (cylinder bank 1 to 4)

CAUTION

The oxygen sensor cable can be damaged if twisted.

- Change in emissions.
- Check Engine light comes on.

-> Always expose oxygen sensor cable so that the wire can turn when unscrewing or screwing in the sensor.
-> Do not kink cable.

3. Route oxygen sensor cable around the exhaust manifold and generator and clip it in. => Oxygen sensor on naturally aspirated engine M48/01, cylinders 1 to 4





Oxygen sensor on naturally aspirated engine M48/01, cylinders 1 to 4









Exhaust manifold on naturally aspirated engine M48/01, cylinders 1 to 4





Cylinder bank 5 to 8
1. Carefully coat the thread of the oxygen sensor with 000.043.207.07.
6. Use a suitable tool to screw the oxygen sensor into the exhaust manifold by hand from below. -1- Screw on oxygen sensor correctly. => Tightening torque: 45 Nm (33 ftlb.)+/-5 Nm (+/-3.5 ftlb.)





View of oxygen sensor in exhaust manifold from below (cylinder bank 5 to 8)

CAUTION

The oxygen sensor cable can be damaged if twisted.

- Change in emissions.
- Check Engine light comes on.

-> Always expose oxygen sensor cable so that the wire can turn when unscrewing or screwing in the sensor.
-> Do not kink cable.

7. Route oxygen sensor cable around the exhaust manifold and clip it in. => Oxygen sensor on naturally aspirated engine M48/01, cylinders 5 to 8





Oxygen sensor on naturally aspirated engine M48/01, cylinders 5 to 8









Exhaust manifold on naturally aspirated engine M48/01, cylinders 5 to 8





Subsequent work
Cylinder bank 1 to 4
1. Fit primary catalytic converter. -> 267619 Removing and installing primary catalytic converter on V8 4.8-litre DFI engines - section on "Installing" 267619 Removing and installing primary catalytic converter on 4.8-litre V8 DFI engines
2. Fit heat protection panel on the generator. -arrows at front-





Heat protection panels on V8 naturally aspirated engine

3. Fit air-cleaner element.Cylinder bank 5 to 8
1. Fit air-cleaner element.
6. Fit underbody panelling under the engine.