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Camshaft Position Sensor: Description and Operation

PURPOSE
The camshaft sensor produces a signal indicating the beginning of the intake stroke for #1 cylinder. The signal is used to determine injection timing. Injection begins with #1 cylinder on the intake stroke and then follows the firing order. If this signal is not present, injection will not begin and the engine will not start. If this occurs, a code 17 will set.

Camshaft Position Sensor (CMP):





LOCATION AND OPERATION
The camshaft sensor is a hall-effect sensor installed at the left of the front cylinder head. The tip of the sensor comes very near a reluctor "pole" piece, cast as part of the camshaft. When this pole piece passes the sensor tip, the disturbance in the sensors magnetic field turns the hall-effect switch "OFF" and "ON" again, producing a signal that the computer can read.