Kia Optima: Knock Sensor (KS). Description and OperationWhen 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.

Installation
Knock Sensor (KS). SpecificationsComponent Location (2)
1. FOB holder
2. Door outside handle
3. Trunk lid open switch
4. FOB key
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Replacement
1.
Loosen the wheel nuts slightly.
Raise the vehicle, and make sure it is securely supported.
2.
Remove wheel nuts, front wheel
and tire from front hub.
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Climate Control Air Filter. Repair procedures
Replacement
1.
Disconnect the damper (B) from
the glove box (A).Remove the glove box lift (C).
2.
Remove the filter cover with
pushing the knob.
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