Q: What is the purpose of the crankshaft position sensor (CKP) on Ford Excursion?
A: The crankshaft position sensor (CKP) determines the timing on each cylinder for the fuel injectors and ignition system. The crankshaft sensor is mounted near the crankshaft pulley. A problem in the crank-shaft sensor circuit will set a diagnostic trouble code. Make sure the ignition key is in the OFF position. Remove the air conditioning compressor. On 2004 models it is not necessary to remove the compressor. It is possible to simply lower the compressor about an inch for access to the sensor. Raise the vehicle and support it securely on jackstands. Working under the vehicle, disconnect the crankshaft position sensor electrical connector. Remove the bolt and detach the sensor. Installation is the reverse of removal.