Knock Sensor: Description and Operation

Knock Sensor (KS):

PURPOSE
The Knock Sensor (KS) is an electronic device capable of measuring vibration and converting it to an electrical signal reflecting engine knock.The ECA uses the signal to alter ignition timing and turbo boost pressure when engine knock is detected.

LOCATION
Engine block near oil pressure switch.

OPERATION
When engine knocking occurs due to overboost by the turbocharger system, the ECA alters ignition timing and boost pressure to reduce the occurance of spark detonation and engine damage. The sensor signal is first filtered by the knock control unit to eliminate normal engine vibration signals before reaching the ECA.