Sunday, I exit the highway and at the next stop sign, the car was chugging and missing. It was a coil pack. In 97, Ford was using two coil packs - with two coils in each pack. Each coil fired two cylinders - one on the compression stroke and the companion cylinder (waste spark) on the exhaust stroke. So, when a coil in one of the packs goes, you have a miss in two cylinders. The V8 instantly becomes a V6. The removal/install process took all of 5 minutes, just remember to mark plug wire location on the pack before removal. Four 7mm bolts and it's smooth again. Just passing on my experience. Maybe it will help somebody else.