A musty odor may be noted from the heating, ventilation and AC (HVAC) system after sitting for two hours or more due to condensation in the heater case. Our technicians tell us that a cleaner is available for the heater case and the drain system should be checked for debris.Google+
Car Problem Reports
Volkswagen Golf TDI Odor from HVAC vents
Volkswagen Golf TDI Problem
I also notice this smell.
Visitor, 2012 Volkswagen Golf TDI
very rank odor coming from a/c vents when a/c isn't on.