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Knock Sensor: Description and Operation

Knock Sensor

Knock Sensor (KS):





The Knock Sensor (KS) is used to detect engine detonation (spark knock). As a result, a voltage signal is sent to the PCM which retards the ignition timing as necessary.

The Knock Sensor (KS) is a tuned accelerometer on the engine which converts engine vibration to an electrical signal. The PCM uses this signal to determine the presence of engine knock and to retard spark timing.