- Be sure the ignition switch is OFF. Disconnect the sensor electrical connector and the ECM connector. Connect an ohmmeter.
- Measure the resistance between the sensor harness and ground at the sensor signal circuit.
- Measure the resistance between the sensor signal circuit and the ground circuit.
- Specification is infinite.
- If resistance indicates an open circuit, install a known good sensor. Recheck, if the problem is corrected replace the sensor
- Check the sensor torque. It should be 11-18 ft. lbs.
- If the sensor is still not functioning, replace it with a known good component.
- Recheck the sensor.
The knock sensor is used to detect engine vibrations caused by preignition or detonation and provides information to the ECM, which then retards the timing to eliminate detonation.