The crankshaft position sensor on the Cadillac DeVille is located behind the crankshaft pulley. It works with a 58-tooth reluctor wheel on the crankshaft. The programmable control module reads the crank sensor signal circuit at 12 volts. As each reluctor wheel tooth passes the sensor, the sensor is grounded, which creates a square wave signal. The PCM uses the wave signal to determine rpm and location of the crankshaft. It uses the signal to synchronize ignition timing, fuel injector firing and knock control. If the crankshaft position sensor malfunctions, the DeVille will not start.
Disconnect the wiring harness connector from the crankshaft position sensor by pulling the tangs on the side of the connector away from the plug and pulling the plug off the sensor.
Unbolt the sensor's retaining bolt, using the appropriate socket. Remove the sensor and its O-ring from the block.
Clean the mating surface on the block with a rag. Ensure that the new O-ring is on the new sensor. Install the sensor and tighten the retaining bolt firmly. Do not over-tighten the bolt, as you will damage the sensor.
Plug in the wiring harness connector, ensuring that it snaps into place.
