On my 2003 F-250 S.D. 7.3 liter diesel full cab, I am having stress with the cruise control. Occasionally the speed control will drop out with the icon still lite in the cluster. Other times the engine will stall out completely and will only restart when the ignition is turned off fully for a few seconds. This problem does not occur when using the acelerator pedel. The delearship(s) can't find the problem because it doesn't leave an error code and never does it while they have it. Any ideas out there?????