What is the most common issue with the Audi 80's coolant system?

I have been experiencing frequent overheating in my Audi 80 and suspect it may be related to the coolant system. Can anyone shed some light on what the most common issue is and how to fix it?

The most common issue with the Audi 80's coolant system is a leak in the radiator. This can be caused by aging or damage from debris on the road. The best solution is to replace the radiator.

Another common issue is a faulty thermostat. This can cause the engine to overheat or run at too low a temperature. A simple fix is to replace the thermostat.