Knock Sensor

The Knock Sensor (KS) is a piezoelectric device which detects abnormal engine vibrations (spark knock) in the engine. This vibration results in the production of a very low AC signal, which is sent from the KS to the KS module (integral to PCM). The PCM then retards ignition timing until the engine knock ceases. Two KS are used on some models.

A fault in the KS circuit may set a DTC. See appropriate SELF-DIAGNOSTICS article. When a related DTC is not present and the KS system is the suspected cause of a driveability problem, perform functional check of KS system. See appropriate SYSTEM & COMPONENT TESTING article.