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Home >> Kia >> 2009 >> Sorento Base, A5SR2 >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System >> Knock Sensor (KS) >> Repair Procedures >> Inspection >> Function And Operation Principle
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Function And Operation Principle

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 PCM and the PCM retards the ignition timing. If the knocking disappears after retarding the ignition timing, the PCM will advance the ignition timing. This sequential control can improve engine power, torque and fuel economy.

Fig 1: Identifying Knock Sensor (KS)
G06408066Courtesy of KIA MOTORS AMERICA, INC.
Fig 2: Exploded View Of Knock Sensor (KS) Components
G06408067Courtesy of KIA MOTORS AMERICA, INC.