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Sunday, August 2, 2009

Engine Speed Sensor

The engine speed sensor sends information to the computer telling it how fast the car is traveling. The engine speed sensor is designed to record the rate at which the crankshaft is spinning. This sensor consists of a toothed metal disk mounted on the crankshaft and a stationary detector that covers a magnetic coil that the current passes through. As the metal teeth move past the coil, its magnetic field is disturbed. This causes a stream of pulses in the current. The computer can calculate engine speed from the number of rotations of the crankshaft. The number of rotations are reported by the frequency of the pulses from the engine speed sensor.