OK, I know that Ford has had big problems with their spark plug coil packs on the 5.4 motors, but can anyone tell me what causes them to go bad? Other vehicles use this type of setup without any problem. What is the deal with the Fords. I'm tired of replacing mine all the time.

 

How many have you replaced, and in how many miles?

 

I've replaced 5 or 6. The first one sent bad a around 40k miles. I usually loose 1 a year. I've actually had to replace 2 this month.