Envoy 2WD V8-5.3L VIN P (2004)
Camshaft Position Sensor: Description and Operation
CAMSHAFT POSITION (CMP) SENSOR
The CMP sensor is also a magneto resistive sensor, with the same type of circuits as the CKP sensor. The CMP sensor signal is a digital ON/OFF pulse,
output once per revolution of the camshaft. The CMP sensor information is used by the PCM to determine the position of the valve train relative to the
CKP.
CAMSHAFT RELUCTOR WHEEL
The camshaft reluctor wheel is either pressed onto the camshaft or part of the timing gear depending on the application. The feature-or target- is read in a
radial or axial fashion respectively. The wheel is a smooth track, half of which is of a lower profile than the other half. This feature allows the CMP
sensor to supply a signal as soon as the key is turned ON, since the CMP sensor reads the track profile, instead of a notch.
