Crankshaft Position Sensor (Liberty - 2.4L)
On 2.4L, the Crankshaft Position (CKP) sensor is mounted into the right front side of the cylinder block. See Fig 1 . It is positioned and bolted into a machined hole. Engine speed and crankshaft position are provided through the CKP sensor. The sensor generates input pulses that are 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 (targetwheel) is a part of the engine crankshaft. See Fig 2 . This tonewheel has sets of notches at its outer edge. The notches cause a pulse to be generated when they pass under the sensor. The pulses are the input to the PCM.