Knock Sensor: Description and Operation

Location

Sensor mounted in engine block.

Purpose

Sensor informs The Control Module detonation has occurred.

PCM retards timing until detonation is no longer detected.

Knock Sensor Operation:

Operation

Sensor generates a signal when spark knock, (pre-ignition, detonation, or pinging) occurs in combustion chamber, (due to vibration of the piezo electric crystal).