Impreza Sedan AWD F4-1820cc 1.8L SOHC (1993)
Camshaft Position Sensor: Description and Operation
Cam Angle Sensor
PURPOSE
The camshaft position sensor generates a frequency signal used by the ECM to determine piston location.
LOCATION
The sensor is located on the front of the engine, at the left camshaft support.
Cam Angle Sensor Output Signal
OPERATION
The sensor generates a signal pulse whenever the engine is rotating. As a tooth on the camshaft pulley passes behind the sensing head, a small
electrical pulse is generated.
The signal is returned to the ECM and combined with the signal from the crank angle sensor. By combining the signals, all cylinders can be
identified.