Last night while on the prowl for some Krispy Kreme Donuts, I noticed my temp gauge moving fast towards the red zone. I was driving the car for about 30-45 minutes prior to this happening. I pulled over and popped the hood, lots of steam and bubbles were coming out of the radiator. It has been working fine for a while now, but something is wrong with it. How do I find out if it has air in the system?