Knock Sensor: Description and Operation

Knock Sensor:

PURPOSE
The Knock Sensor (KS) detects engine knocking conditions and sends a signal to the Powertrain Control Module (PCM). The PCM then retards the ignition timing to compensate for the condition

OPERATION
If a knocking vibration from the engine block occurs, its pressure is applied to the piezoelectric element of the KS. This vibrational pressure is then converted into a voltage signal which is delivered to the PCM. The KS is attached to the engine block between the cylinder banks. The Malfunction Indicator Lamp (MIL) will not be illuminated for a KS malfunction.