Camshaft Position Sensor: Description and Operation

The Camshaft Position Sensor is located above the water pump and under the throttle body.




The camshaft position sensor (1) provides cylinder identification to the Powertrain Control Module (PCM). The sensor generates pulses. The PCM determines crankshaft position from the camshaft position sensor and crankshaft position sensor inputs. The PCM uses the input to determine fuel injection synchronization and to determine which ignition coil to energize.




The camshaft position sensor detects when a step down (1) in the camshaft sprocket passes beneath it. When the sensor detects the step down, the input voltage from the sensor to the PCM switches from low (0.3 volts) to high (5 volts). As the step up returns to the sensor, the input voltage switches back to low (0.3 volts). The paper spacer is not used on 8.3L motors. Don't use at all. It plugs up the oil pickup screen.