Odor from HVAC vents on Volkswagen Passat

Problem Description and Possible Solution

Condensation may develop in the heater case which can cause a musty odor from the heating, ventilation and AC (HVAC) system.  Our technicians tell us a cleaner is available for the heater case. Also, the drain system should be checked for debris.

Problem Data
RepairPal Verified
Average mileage: 52,539 (5,500–109,000)
10 model years affected: 2001, 2005, 2006, 2007, more2008, 2009, 2010, 2013, 2014, 2015
30 people reported this problem
Viewing 1 - 14 of 14 comments
Yes, I have a 2005 Passat, and have noticed over the past few weeks of a stale, musty smell coming through both dashboard and windscreen vents.
It smells like air moving across damp insulation, and when the sunlight is in the car, the vapour is visible through the vents, plus it fogs up the inside of the windscreen.
I noticed this smell coming from the vents. First I am thinking this can not be healthy for my family and myself, so I took the car to the dealership. I was told it had something to do with the pollen filter. I was not really buying that. They said if the problem still exists I will have to have a cleaner put into the HVAC system, they also mentioned this is not under warranty. WHAT bumper to bumper 3 years. I am thinking don't deal with this company again. Only 11,000 wow
It's the "Beasts" not sure if anyone has seen that Seinfeld episode but that's what has been happening to my 2012 Passat. I love the car but the smell is terrible, we have spent over a $1,000 dollars with our dealer trying to flush it out. This apparently has been a problem with VW since 2009 why should I have to be paying for it. The problem only seems to be persistent in the warmer weather which indicates to me its something to do with the aircon.
The dealer told me other then remove the upholstery thinking the smell has permeated into the interior, they don't know what to do. Thanks VW, I wonder what they will charge me for that.
Does anyone have a solution to this "Beastly" smell.
I bought a 2015 VW Passat in October 2914. After I had it about aprox 5500 miles it developed an odor coming out of the vents like Cat urine. A fix was tried by VW but it was only a cover-up. On Sep 2, 2015 my Passat was totaled. I bought another about a month later. Now at 5500 miles the odor problem with the same cat urine smell has happened again with the new car. Different dealer. I am taking it in tomorrow.
musty smell in cabin. Not fixed as yet
When I turn the AC on it smells like pee. Diminishes over time but never goes away.
Passat heat has moldy/musty smell
Bad odor from the vent every time I turn my car on
Musty smell when AC is turned on.
This happens every spring. Tired of paying VW to do whatever "treatment" they have
stinky stinky car!! We've cleaned EVERYTHING inside, but the odor persists. We've flushed the hvac system four times, changed the interior filters, pulled up the carpet and cleaned weird moldy stains. Don't know what else to do!
Nasty smell for vents, mostly when using fresh air inlet. Not as bad when using AC with recirculation enabled.
Musty smell from a/c unit upon every use.