I have a 2004 Vitara v6 with 50,000 miles on it. After running some errands around town a week ago I parked it in my driveway. A little later I tried to start it and nothing happened except "click". I had it towed to my hometown mechanic and he says the engine is seized. All vitals were OK when I turned the engine off - no lights on the dash, no noises, no smells, nada. It was working fine and in the space of an hour or two it seized up sitting in my driveway. How could this happen so quickly? Do I need another opinion?