Not sure what, but something really bad went wrong with our Mazda3 yesterday. We had just loaded up to go to a B-Day party and were going up a moderately steep hill about one block from our place, and there was a popping sound. The car seemed to lose some power and when I looked in the rear view mirror there was a lot of white smoke behind us. I immediately pulled over and turned off the car. Nothing out of the ordinary was visible inside the engine compartment; so, I turned the car back on, and immediately drove it home, parked, and turned it off. Testing the car later that day, the car produced lots of smoke after about 30 seconds of running. Ive decided I wont run it further and need to get it towed to a shop. So, any ideas of what might be wrong with it? Im guessing a blown head gasket or a blown ring, but Ive never experienced or seen either one; so, I could be completely wrong. Heres the worst, we are just 3K miles over power train warranty. If it is a head gasket that sort of failure should not happen with only 63K miles. It seems like Mazda should cover this. Any recommendations for getting that to happen? I need ideas and suggestions! Thanks!