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Engine Control Components

Engine Control Components

Camshaft Position (CMP) Sensor

The CMP sensor detects the position of the camshaft. The CMP sensor identifies when piston number 1 is on its compression stroke. A signal is then sent to the PCM and used for synchronizing the sequential firing of the fuel injectors. Coil on plug (COP) ignition applications use the CMP signal to select the correct ignition coil to fire.

Vehicles with two CMP sensors are equipped with variable camshaft timing (VCT). The second sensor is used to identify the position of the camshaft on bank 2.

There are two types of CMP sensors: the 2-pin variable reluctance type sensor and the 3-pin Hall-effect type sensor.

Typical Variable Reluctance CMP Sensor:




Typical Variable Reluctance CMP Sensor

Typical Hall-effect CMP Sensor:




Typical Hall-effect CMP Sensor