Manuals through 2025 now available!

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LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Knock Sensor: Description and Operation

PURPOSE
The Knock Sensor Signal informs the Engine Control Module (ECM) of predetonation or "ping".

OPERATION
Predetonation of a cylinder "charge" causes a shock wave to be sent through the engine block assembly. The piezoelectric crystal that is the Knock Sensor reacts to mechanical force associated with shock wave by discharging a small electric current. This signal is then sent to the ECM which will then retard the ignition timing.