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Camshaft Position Sensor: Description and Operation

Camshaft Position (CMP) Sensor:






PURPOSE
The Camshaft Position (CMP) sensor detects the position of the camshaft when piston number one is at a specific top dead center point of its compression stroke. A signal is then supplied to the Powertrain Control Module (PCM) and used for synchronizing the firing of sequential fuel injectors. The input circuit is referred to as the Cylinder Identification (CID) input or circuit.

OPERATION
The CMP sensor is a Variable Reluctance Sensor (VRS) activated from a high point on the oil pump sprocket at camshaft speed. The Camshaft Position (CMP) sensor is located behind the inner timing belt cover and mounted on the oil pump assembly.