Alright so I'm having problems with my audi. Every time I start my audi, get it warmed up, and drive for 30 seconds to a minute, my car starts to overheat really badly. It will go from warm to hot without going above 45 mph. I have replaced the thermostat in the hose, and it still happened. Anyone know why it's still overheating?

 

Most likely a shot water pump, its not circulating the coolant and its causing it to overheat. Friend had the same problem, car would warm up as normal but continue to heat up past 90c.