My son has a 97 XLT 4 cyl, auto that has an intermittent problem with starting. When he turns the key, the truck either starts right off, or he gets a single click and nothing further. The battery is fully charged. If he waits 15 minutes or so, it will often start right up as if nothing was wrong. I've noticed that it happens more on cold days or days when it has been raining, so I suspect that there is some sort of short that is exploited with moisture from rain or condensation. I had to pick him up at work the other night when it was raining because it wouldn't start. The next day we returned after the sun had warmed the truck up and it started right up.