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Home >> Kia >> 2011 >> Forte LX, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System >> Knock Sensor (KS) >> Description And Operation >> Description
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Description And Operation: Description

Knocking is a phenomenon characterized by undesirable vibration and noise and can cause engine damage. Knock Sensor (KS) is installed on the cylinder block and senses engine knocking.

When knocking occurs, the vibration from the cylinder block is applied as pressure to the piezoelectric element. When a knock occurs, the sensor produces voltage signal. The ECM retards the ignition timing when knocking occurs. If the knocking disappears after retarding the ignition timing, the ECM will advance the ignition timing. This sequential control can improve engine power, torque and fuel economy.

Fig 1: Knock Sensor & Connector
G07367826Courtesy of KIA MOTORS AMERICA, INC.