The water pump is defective, causing overheating. It has been recalled.

I talked to a friend, and despite working on cars his whole life, he's never heard of a water pump with a plastic impeller. ...it just wears out, and starts slipping on the motor shaft. With no water pump, the car has no cooling, and therefore cannot be driven (without overheating the engine anyway). ALL volkswagens with plastic impellers will face this issue.