I've got a 2014 NMS, 1.8T, 133,000 miles. My heater core went bad, which I can accept. I even realize that with the recall VW had on this issue, I'm past the mileage, so I have no problem paying for a new one out-pf pocket. However, what's VERY puzzling and frustrating is that my dealership has replaced 2 heater cores in the past month and the same problem (no heat on the passenger side) recurs within minutes of their "test drive" after installation. They keep flushing my cooling system and it's now so clean that it's probably crystal clear, but the best thay have been able to do is get very nominal heat on that side while the driver's side gets as hot as Calcutta. The service advisor says this is one of the worst cases of this issue he's ever seen. This makes no sense to me. I asked him: Is there some aftermarket brand of heater core that will fit this generation of Passat that won't have these problems? He says no, but has anyone else had to deal with this?