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Camshaft Position Sensor: Description and Operation

DESCRIPTION
The Camshaft Position (CMP) sensor, located in the distributor, consists of a signal generator and rotor.

OPERATION
As the signal rotor turns, AC voltage is generated in the CMP sensor which provides a digital signal. This signal (5 pulses/revolution) is sent to the Powertrain Control Module (PCM) where it is used to distinguish individual cylinders and to calculate engine speed. The CMP signal is also one of the inputs used in determining when to energize the fuel injector.