Camshaft Position Sensor | Function , types ,Working

CAMSHAFT POSITION SENSOR

The camshaft position sensor monitors the rotation of the camshaft, specifically targeting when valves open and close. Most camshaft sensors are mounted just above a notched ring on the camshaft. Most of these camshaft sensors will use a magnet to produce or vary an AC electronic signal that is used in conjunction with a crankshaft position sensor to determine when a position approaches top dead center (TDC) on the compression stroke. This information will help to fine tune spark timing and injector pulse.

Camshaft position sensor is also called cylinder identification sensor or phase detector.

In consecutive fuel injection systems, ECU must determine which cylinder to fire next. This information is provided from the cylinder identification sensor. During the engine rotation the sensor sends a signal to the onboard controller whenever the first cylinder is at the top dead center (TDC).

Thus, the duration of the pulse injection is estimated. In simultaneous fuel injection systems, the onboard controller does not identify the cylinders and the firing order, because this is not necessary for the system to operate. When a crankshaft or distributor advance ignition signal appears, the exact cylinder is detected by recognizing the mechanical positions of the crankshaft, camshaft, valves or the distributor shaft.

Functions of Camshaft position (CAM) sensor:

To determine which cylinder is in its power stroke, while the car’s computer (for example) monitors the rotating position of the camshaft which is relative to the crankshaft position using a camshaft position (CMP) sensor. It will use this information to adjust the spark timing and the operation of the fuel injectors.
The CAM sensor or camshaft position sensor’s role is to signal the ECM the camshaft position. The crank and cam sensor operates in sync with eachother. The CAM sensor is frequently used in determining which injector to fire in a sequential system and for the COP or coil on-plug ignition systems coil firing event.