Knock sensor — general description

The knock sensor is located in the cylinder block behind the oil filter. The sensor performs the main function in the electronic ignition control system (ESC). It reacts to excessively high vibration in the engine. The sensor produces an output signal in the form of a voltage that rises as the detonation increases. The signal from the sensor is fed to the PCM unit, and on command from the unit, the ignition is delayed by angles up to 10°to compensate for detonation. A detailed description of the ESC system is provided in section 6 of this chapter.