Hey.
Jazzman, the best thing to do is probably put in a new set of fogs, assembly and all. I found that once they start popping, it never ends. I got a set at Crappy tire for 40.00, although it took me 5 hours to do (4 and a half learning to do the first one and half an hour for the second one). They work nicely and didn't cost an arm and a leg. Or go to Ford and see about a new set,
probably about $100 or so. Good Luck