[johnsonwingnut]

Sounds like a coil on plug gone bad. If the engine light is on you can take it to a Autozone or other parts store for a code read. Coil on plug are about $98.00 at Ford dealer. Slightly less at auto parts store,depending on brand replacement.

Each plug on the V-6 has a seperate coil that sets on top and boots over each sparkplug, thus the "coil on plug" name. Or the wire lead to one of the coil on plugs is shorted/bad. The code read will tell you which one is causing malfunction or if it is something else.