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Knock Sensor (KS) Sensor

Knock Sensor (KS):




A Knock Sensor (KS) system is used in order to control spark knock. The KS system is designed to retard spark timing up to 20 degrees in order to reduce spark knock in the engine. This allows the engine to use maximum spark advance to improve driveability and fuel economy.

The knock sensor system is used to detect engine detonation. The knock sensors produce an AC voltage which is sent to the PCM. The PCM retards the spark timing based on signals from the KS sensors. The amount of AC voltage produced by the sensors is determined by the amount of knock. The PCM then adjusts the Ignition Control (IC) to reduce the spark knock.