Operation CHARM: Car repair manuals for everyone.

Knock Sensor: Description and Operation

Knock Sensor:





PURPOSE
The knock sensor's piezoelectric element detects engine detonation. It sends a voltage signal to the PCM.

Detonation Sensor Location:





LOCATION
Attached to the engine block between the cylinder banks beneath the intake manifold.

CONSTRUCTION
The knock sensor, consists of a (3) housing a (4) piezoelectric crystal mounted on a (5) threaded sleeve between (6) two connector strips. One side of the assembly is fitted with a (7) damping weight and (8) spring washer secured by a (9) nut.