Question

2007 Toyota Camry with engine code P0328 Knock Sensor. What is a Knock Sensor?

Answer 1

A knocking vibration from the cylinder block is sensed as vibrational pressure by the Knock Sensor. This pressure is converted into a voltage signal and sent to the ECM. The ECM uses the Knock Sensor signal to control the 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 vibration is applied to them. The piezoelectric element in the Knock Sensor is tuned to the engine knock frequency.

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

Read More: https://www.autocodes.com/articles/23/knock-sensor.html

Answer 2

Hi there,

The knock sensor is a sensor that the computer uses to determine the timing advance when the engine begins to ping at low speed. This is a common issue with unleaded fuel so the sensor is installed to help prevent that.