A few days ago, I took a short trip, and 30 miles into the trip, the vent system started blowing hot for about 5 minutes, then went back to normal. It was a nice day, and I was running 70 mph with top up, no a/c, and the heat control way to the left. 2008 Redline, stock, 64k miles. No unusual temperatures, no puddles when I parked, and no apparent loss of coolant. Is this a warning of the dreaded water pump failure?