Knocking is a phenomenon characterized by undesirable
vibration and noise and can cause engine damage. The two Knock Sensor
(KS) are installed inside the V-valley of 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.
Inspection
1.
Check the signal waveform of the CMPS and CKPS using the GDS.
Specification: Refer to “Wave Form”
Removal
•
DON''T remove the camshaft position sensor while the engine
is running or right after engine is turned off.
Description
1.
The photo sensor is located at the center of defrost nozzle.
2.
The photo sensor contains a photovoltaic (sensitive to
sunlight) diode. The solar radiation received by its light receiving
portion, generates an electromotive force in proportion to the amount of
radiation received which is transferred to the automatic tem