Knock Sensor: Description and Operation

Knock Sensor:

PURPOSE AND LOCATION
The knock sensor's piezoelectric element detects engine detonation. It sends a voltage signal to the ECM. It is located on the engine block under the intake manifold.

CONSTRUCTION
(C) 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.