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Home >> Hyundai >> 2011 >> Azera GLS >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System Components >> 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) senses engine knocking and the two sensors are installed inside the V-valley of the cylinder block. When knocking occurs, the vibration from the cylinder block is applied as pressure to the piezoelectric element. At this time, this sensor transfers the voltage signal higher than the specified value to the ECM and the ECM retards the ignition timing. 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: Identifying Knock Sensor
G07249692Courtesy of HYUNDAI MOTOR CO.