So I changed the Cap a couple of weeks ago and it's still leaking. This is borderline annoying right now, the tank was bought BRAND NEW from the BMW Dealership. I am afraid they won't exchange it but I will try calling them or contacting them.
* I checked all hoses, they all seem fine.
The leak comes right from the top but it's minor, it's enough to build up and stay on top of the tank... the layer of the liquid fluctuates but you can def see it.
Like I said, this is just annoying. I'm already thinking I have to change it again and when I did it last month, it was messy messy.