I have a 02 Ford Explorer with a 4.0 V 6 engine. Twice in the last couple of weeks when I would start it, it acted like the battery was dead. When I first turned the key it barely turned the engine, then I turned the key again and it was like it was dead. I then turned the key again and it started fine. It had the original battery so I changes it the other day. It did this once with the old battery and once with the new one. Could this be the key switch, alternator, power pack or something else. any advice would be greatly appreciated. Thanks!