I have been having the same problem on my 01 4.4.

From reading through all 12 pages it seems the first thing I should try is cleaning/replacing the ignition switch.

Does anyone have the part number for this?

If the switch is located in the steering column, do you access it from inside the vehicle?

My X quite often also makes a loud, embarrasing and strange rattling sound when it does actually start, sounds like something is loose. Anyone else have this happen?