Removing and Installing Oxygen Sensors In Front of Catalytic Converter

Removing And Installing Oxygen Sensors In Front Of Catalytic Converter

Tools







Preliminary work

Preliminary work: Removing oxygen sensors ahead of catalytic converter







ATTENTION:
Danger of burns from hot exhaust system.
- Only remove the exhaust system once it has cooled down.
- Wear protective gloves.

NOTE: Please read the most important working regulations and warning notes.

1. Move bonnet to service position using bonnet stay 9704.
2. Put on the protection covers.
3. Remove right-hand engine compartment covers.
4. Pull the design cover vertically upwards and off.







Tools and materials

Tools - oxygen sensor







Removing oxygen sensors ahead of catalytic converter

ATTENTION:
Material damage can be caused by interchanged oxygen sensors.
- Change in emissions.
- Check Engine light comes on.
- The connector color of the oxygen sensor cable for the oxygen sensor behind the catalytic converter must match the color of the oxygen sensor cable plug of the oxygen sensor ahead of the catalytic converter in the same exhaust assembly (brown to brown and black to black).
- Do not interchange oxygen sensors.

NOTE:
- Cable plugs 1 and 2 belong to the oxygen sensors behind catalytic converter, while plugs 3 and 4 belong to the oxygen sensors in front of catalytic converter. The colors of the cable plugs are the same for each exhaust assembly.
- Mark oxygen sensors as you unscrew them so that the oxygen sensors are not confused.







ATTENTION:
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 plugs of oxygen sensors ahead of catalytic converter -3 and 4- and expose them.












2. Unscrew both oxygen sensors with a ring or open-ended wrench (a/f 22) -1-.







Installing oxygen sensors in front of catalytic converter

Installing oxygen sensors ahead of catalytic converter

ATTENTION:
Material damage can be caused by interchanged oxygen sensors.
- Change in emissions.
- Check Engine light comes on.
- The connector color of the oxygen sensor cable for the oxygen sensor behind the catalytic converter must match the color of the oxygen sensor cable plug of the oxygen sensor ahead of the catalytic converter in the same exhaust assembly (brown to brown and black to black).
- Do not interchange oxygen sensors.

ATTENTION:
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.

NOTE:
- Cable plugs 1 and 2 belong to the oxygen sensors behind catalytic converter, while plugs 3 and 4 belong to the oxygen sensors in front of catalytic converter. The colors of the cable plugs are the same for each exhaust assembly.
- Mark oxygen sensors as you unscrew them so that the oxygen sensors are not confused.

1. Position oxygen sensors by hand and screw in as far as possible.
2. Position oxygen sensors behind catalytic converter -1- by hand and screw in as far as possible.







3. Tighten oxygen sensors using special tool. Tightening torque: 37 ftlb.
4. Lay oxygen sensor cable and press into clips. Fit cable plug -3 and 4-.







Subsequent work

Subsequent work: Installing oxygen sensors ahead of catalytic converter
1. Fit engine compartment covers.
2. Install design cover.







3. Fasten bonnet.