Tacoma PreRunner Extra Cab 2WD L4-2.7L (3RZ-FE) (1998)
Knock Sensor: Description and Operation
The 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.