Knock Sensor

The Knock Sensor detects engine knock and sends a voltage signal to the ECM. The ECM uses the Knock Sensor signal to control timing.

Engine knock occurs within a specific frequency range. The Knock Sensor, located in the engine block, cylinder head, or intake manifold is tuned to detect that frequency.

Inside the knock sensor is a piezoelectric element. Piezoelectric elements generate a voltage when pressure or a vibration is applied to them. The piezoelectric element in the knock sensor is tuned to the engine knock frequency.

Knock Sensor Location

Knock Sensor



The vibrations from engine knocking vibrate the piezoelectric element generating a voltage. The voltage output from the Knock Sensor is highest at this time.

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  • Tom
    Where is the knock sensor located on a 2003 toyota corolla?
    3 years ago
  • tewelde mehari
    WHAT IS A KNOCK SENSOR ON A 2000 Toyota Corolla?
    3 years ago
    Where is the knock sensor located on 97 celica?
    3 years ago
  • veera
    Where is the knock sensor on a 1997 toyota corolla?
    10 months ago
  • mirabella hogpen
    What is the knock sensor for toyota prius ?
    10 months ago
  • malva
    Where the knock sensor connected of toyota rav4 2004?
    9 months ago
  • kaleb
    What should the resistance of my 2013 corolla engine knock sensor be?
    8 months ago
  • silke pfaff
    Where is knock senor on 2010 toyota corolla?
    5 months ago
  • rebecca
    Where the knock sensor is located in 2005 toyota corolla?
    4 months ago
  • Charles
    Where the knocking sensor is located on 1995 to 1996 corolla 1.6 engine?
    8 days ago

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