Knock Sensor: Service and Repair

Fig. 3 Type I and Type II Knock Sensors:

The two different types of knock sensors (Type I & II) have different torque and resistance specifications, so proper identification before testing or replacing is very important.

1. Disconnect battery negative terminal before loosening or tightening the knock sensor.
2. Do not use any washers on the mounting bolt.
3. Knock sensor mounting bolt torque is critical and specifications must be strictly followed.
4. Check to see that the mounting bolt is clean and free of burrs that could affect torque values.
5. Check to see that the mounting boss on the engine block is free of dirt and excess paint that could prevent good contact with the knock sensor.

TYPE I
Torque 11 +/- 1 Nm (8 +/- 1 ft. lb)
Resistance approx. 300k ohms.

TYPE II
Torque 20 +/- 5 Nm (14 +/- 4 ft. lb.)
Resistance infinite (open circuit)