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Knock Sensor: Description and Operation











OPERATION
The knock sensor generates a voltage proportional to the magnitude of cylinder block vibration due to knocking and inputs it to the engine control module. Based on this signal, the engine control module provides retard control of the ignition timing.

TROUBLESHOOTING HINTS
When knocking occurs while driving under high load conditions, the following problems are suspected in addition to the knock sensor itself.
(1) Inappropriate ignition plug heat range
(2) Inappropriate gasoline
(3) Incorrectly adjusted reference ignition timing