Previa Van LE 4WD L4-2438cc 2.4L DOHC SC MFI (1997)
Knock Sensor: Description and Operation
CIRCUIT DESCRIPTION
A knock sensor is fitted to the cylinder block to detect engine knocking. This sensor contains a piezoelectric element which generates a voltage
when it becomes deformed, which occurs when the cylinder block vibrates due to knocking. If engine knocking occurs, ignition timing is retarded
to suppress it.