CNTHOR is correct that a bad HALL sensor can cause the problem, bu there are so many many more possibilities that may be the cause. The HALL sensors are close to the LAST item I would check. IF you do replace it, DO NO CUT THE WIRES! The pins in the connector can be removed! They were manually installed at assy and with a magnifying glass and a tiny flat blade and straight pins, you can figure out how to release them from the connector they are installed into. This is true for all FORD electrical connectors I have seen.