Knock Sensor

Knock sensor consists of a piezoelectric crystal encased in a metal and plastic housing. Vibrations in engine cause crystal to generate small amounts of voltage. This voltage signal is used by ICU to determine necessary timing retardation.

If knocking is detected, ICU will retard ignition 3.4 degrees. If knocking stops, timing will advance in steps of .54 degrees until it reaches pre-programmed value. If knocking continues, timing can be retarded as much as 12 degrees.

Knock sensor is located on left side of cylinder block, next to cylinder No. 3. Knock sensor connector is located on a bracket next to distributor.