I have a 97 expedition.5.4L engine. For the past year and a half the check engine light comes on and goes off. When it is on the engine runs rough. The diagnostic was a bad coil. I call BS due to the fact that the problem will fix and light goes off. I have never seen a coil fix itself. So anyways, I was wondering if there was anyone out there with ideas. Has 112k miles on it. I keep good maint. care of it. I saw a post about someones 94 bronco I think and he described similar prob. Was the throttle position sensor which is my hunch. Any help is appreciated.