Knock Sensor: Service and Repair

Removing And Installing Knock Sensor

Tools







Technical values







Preliminary work
1. Disconnect battery.
2. Remove pressure pipe.
3. Remove air cleaner housing.

Removing knock sensor

Removing knock sensor, cylinder bank 1-3
1. Lower the engine.
Lower the engine by max. 40 mm.
Support the engine with a jack and retainer plate P 9592.
Loosen and screw off M12 collar nuts on the engine mounting. Carefully lower the engine using the jack.

2. Remove fuel filter.
3. Remove secondary-air pump.
4. Remove oil-filter console.
5. Remove central intake-air distributor.
6. Remove left intake-air distributor.
7. Remove shut-off valve.
8. Remove additional coolant pump.
9. Remove knock sensor.







9.1. Pull off cable plug -3-.
9.2. Unscrew screw -2- and remove knock sensor -1-.

Removing knock sensor, cylinder bank 4-6
1. Remove throttle housing.
2. Detach and swivel out compressor.
3. Remove knock sensor.







3.1. Pull off cable plug -2-.
3.2. Unscrew screw -3- and remove knock sensor -1-.

Installing knock sensor

Installing knock sensor, cylinder bank 1-3
1. Install knock sensor.

CAUTION:
Knock sensor not installed correctly.
- Risk of engine damage and modified exhaust emissions.

- Strictly observe specified tightening torque for screw.
- Align knock sensor in such a way that the sensor housing and cable plug are not touching.







1.1. Fit knock sensor -1- with screw -2- and align it. Then tighten screw. - Tightening torque: 20 Nm (15 ftlb.)±2 Nm (±1.5 ftlb.)
1.2. Push on cable plug -3-.

2. Install additional coolant pump. - Tightening torque: 10 Nm (7.5 ftlb.)

3. Install shut-off valve. - Tightening torque: 10 Nm (7.5 ftlb.)

4. Install left intake-air distributor. - Tightening torque: 10 Nm (7.5 ftlb.) - Tightening torque: 10 Nm (7.5 ftlb.) - Tightening torque: 30 Nm (22 ftlb.) - Tightening torque: 10 Nm (7.5 ftlb.)

5. Install oil-filter console. - Tightening torque: 0 Nm (0 ftlb.)

6. Install secondary-air pump. - Tightening torque: 10 Nm (7.5 ftlb.)

7. Raise the engine.
Raise the engine to assembly position using a retainer plate P 9592.
Screw in and tighten collar nuts. - Tightening torque: 85 Nm (63 ftlb.)

8. Install fuel pump.

Installing knock sensor, cylinder bank 4-6

CAUTION:
Knock sensor not installed correctly.
- Risk of engine damage and modified exhaust emissions.

- Strictly observe specified tightening torque for screw.
- Align knock sensor in such a way that the sensor housing and cable plug are not touching.

1. Install knock sensor.

CAUTION:
Knock sensor not installed correctly.
- Risk of engine damage and modified exhaust emissions.

- Strictly observe specified tightening torque for screw.
- Align knock sensor in such a way that the sensor housing and cable plug are not touching.







1.1. Fit knock sensor -1- with screw -2- and align it. Then tighten screw. - Tightening torque: 20 Nm (15 ftlb.)±2 Nm (±1.5 ftlb.)
1.2. Push on cable plug -3-.

2. Insert and fit compressor. - Tightening torque: 23 Nm (17 ftlb.)

3. Install throttle housing. - Tightening torque: 10 Nm (7.5 ftlb.)

Subsequent work
1. Install air cleaner housing.
2. Install pressure pipe.
3. Connect the battery.