I have a 2014 Toureg that has started gathering water in the back footwell behind the drivers seat. There is also alot of condensation in the car now particularly the windscreen. Even when hardly driving the car fills up with water and condensation. Also the heating is cold and won't warm. There's alot of rain here and can't work out where the water is coming from and how to stop the leak. My local garage has told me it's ÂŁ2,500 to fix. Any ideas and ways to fix myself?