Crankshaft Position Sensor (4.7L)
The CKP sensor is mounted in the engine block above the starter motor. See Fig 1 . On all engines, engine speed and crankshaft position are provided through the CKP sensor. The sensor generates input pulses that are the sent to the Powertrain Control Module (PCM). The PCM interprets the sensor input to determine the crankshaft position. The PCM then uses this position, along with other inputs, to determine injector sequence and ignition timing. The sensor is a Hall Effect device combined with an internal magnet. It is also sensitive to steel within a certain distance from it.
A tonewheel is bolted to the engine crankshaft. See Fig 2 . This tonewheel has sets of notches at its outer edge. These notches cause a pulse to be generated when they pass under the sensor. Pulses are the input to the PCM.