Knock Sensor

Inspect/Test/Replace

A defective knock sensor may cause engine detonation or reduced spark advance and fuel economy. When a knock sensor is removed and replaced, the sensor must be tightened to its specified torque. If the knock sensor is installed tighter than it should be, it may become too sensitive and provide an excessively high voltage signal, resulting in more spark retard than required. When the knock sensor is installed looser than it should be, the knock sensor signal will be lower than normal, resulting in engine detonation.

To replace the knock sensor:

  • Disconnect the knock sensor wiring connector.
  • Then, unscrew the sensor.
  • Remove the knock sensor.
  • Reverse the procedures to install the part.

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