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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/OPERATION
The knock sensor is a piezo-electric type crystal which converts knocking vibrations into electric signals. If engine knocking occurs, the crystal shakes causing Voltage to be produced. When engine knocking is detected by the engine control module it retards the timing to reduce the detonation. Some reduction in engine power will be noticed with the reduction in timing.