It's your camshaft synchronizer. It will have to be replaced before it causes damage to the cam sensor. If the engine light is not on, then the cam sensor would be fine. The noise is a sign that the bushing in the synchronizer is worn out. Eventually there is enough play in it to allow the rotating tab inside to contact the cam sensor that is mounted on top of it.
dont get the aftermarket dorman replacement get the ford part, thereis a big thread concerning this and also instructions on diy .
check around on the web the prices vary for the ford part bty get the senser at the same time. it is cheap