Servus, I have exchanged the coolant compensation tank today for reasons of preventive maintenance. Many already know the topic, the container can be leaked due to the thermally high load and then the coolant runs on the injectors and ignition coils, which then go defective. There is meanwhile also a changed part number and the part looks different. At first glance an additional damping / relief at the screw-down points and a a kind of drain channel, which now the coolant, which if necessary from the valve in the lid, does not run directly down (to the injectors), but leads back to the front wall. My recommendation would simply have the container replaced when replacing the spark plugs (there it must be removed anyway). Depending on the discount, the cost point for the new container is between 97 and 150 euros. In any case, also the lid, the built-in valve is known for a problem, which This is the result of a reduction in the amount of coolant which can lead to a loss of coolant.