Knock Sensor

Knock sensor detects cylinder block vibrations caused by knocking and sends a signal to Engine Control Module/Powertrain Control Module (ECM/PCM). See Fig 1 or Fig 2 . ECM/PCM retards ignition timing according to strength of knocking.

Fig 1: Locating Knock Sensor (2.4L)

Courtesy of CHRYSLER CORP.

Fig 2: Locating Knock Sensor (3.0L)

Courtesy of CHRYSLER CORP.