Knocking is a phenomenon characterized by undesirable
vibration and noise and can cause engine damage. The two Knock Sensors
(KS) are installed inside the V-valley of the cylinder block and sense
engine knocking.
When knocking occurs, the vibration from the cylinder block is applied as pressure to the piezoelectric element.
When knocking occurs, the sensor produces voltage signal 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.

Other information:
Removal
1.
Turn the ignition switch OFF and disconnect the negative (-) battery cable.
2.
Remove the rear-left wheel & tire and house cover.
3.
Disconnect the canister close valve connector (A).
4.
Disconnect the vent hose quick-connector (B).
5.
Disconnect the vapor hose qu ...
✽ NOTICE
Make sure that all warning lights
are OFF after starting the engine. If
any light is still ON, this indicates a
situation that needs attention.
Supplemental Restraint
System Warning Light
This warning light illuminates:
Once you set the Engine
Start/Stop button to the ...