Bad smell from Air-conditioning

I have had my Legacy for 15 months and have taken it back to the Subaru dealer 3 times because of a mouldy smell from the air-con. It is now back again. In the summer when the air-con is chilling the air it is OK but in the winter when the heater is blowing warm air and the air-con comes on the air smells very stale. I took it to the Subaru dealer before the warranty expired and they have used an antibacterial canestor in the car three times now. It stops the smell for a few weeks and then it comes back again. They have told me that this is not a warranty issue. Has anyone had a similar problem and managed to get a permanent solution?

Has the cabin filter been changed?

I've had this problem. My car had been sitting on the dealer lot for a few months before I bought it and almost immediately I noticed it smelled a little odd. I heard from a post of this board to take water diluted with bleach and spray it in the A/C intake vent (between the hood and the windshield, if you lift the hood) with the air on. I did that for about 15 minutes and the smell was masked the "swimming pool" scent from the bleach water. Unfortunately, that didn't last very long.

 

I asked the dealer and they said there was no reason to replace the cabin filter just yet, since it was somewhat labor intensive to replace. The service tech recommended that I get some Ozium spray and try that. I did, and it smelled better than the bleach water. It seemed to work okay. This all happened around March or April.

 

Over the summer months, the smell seemed to have finally disappeared. Then, back around October or November, as the weather started cooling off, the smell came back. Granted, it isn't as strong as before, but I get it regardless of whether the vent is on, the heat is on, or the A/C is on, and regardless of whether the fan is on recirc or allowing outside air in.

 

If the fan is on recirc, does the air pass through the cabin filter, or does that only happen when letting outside air in?

It sounds to me that you have something growing in the system so replace that cabin air filter and do a cleaning of the remaining parts.

 

Also make sure that the drain works on the heating system so you don't have a pool of water where things can grow.

 

But you may also suffer from a small leak in the heater, so I suggest that you check that.

I have this problem also, though it only started this Christmas after 43k miles

Thanks for the responses. It sounds as if Desertfox has it worse than me. At least mine doesn't smell unless the air-con is on. The Subaru dealer changed the cabin filter and checked the gas level when I first took it to them last January. Once the scent from the antibacterial treatment they put in the car had warn off, about 6 weeks later, the bad smell was back. Over the last weekend I checked that the drain pipe under the car from the heat exchanger was running - it was. I have put another anti-bacterial canestor in the car and worked out how to change the filter myself so I will get a new one in the next few days. I am sure what I have done is only a temporary cure again. I am worried that the heat exchanger may have to come out to get cleaned.

I've heard that there are some drains/overflow/vents in the heater/cooling system that vent to the atmosphere - and if these get clogged, you can get that "stink" because something is now growing.

 

Not sure exactly what they are or where located, but you may want to track this avenue down.

Im pretty sure there is a walkthrough for cleaning that smell out.

your condensate drain is probably clogged holding water by the evaporator coil. But it is probably a good idea to change the cabin air filter as well.

Before we get all technical, are you sure somebody just didnt take a crap in your car without telling you?

For most of us, that is so unlikely as to be unthinkable...

winns makes a product for killing foul odors in ac/heat ducts. its an aerosol, i'll check at work for what the exact name is and maybe you can find it in your area

How stale is stale? To my nose (cue the Princess-and-the-pea soundtrack), air from air-conditioners had always smelled funny, and stale is as good a word for it as any. Not exactly offensive, but kind of annoying... anyone feel the same way? Or have I just been cursed with stinky air conditioners or a hypersensitive nose?

My dealer recommended using Ozium, wich is an aerosol spray. It worked - temporarily. The dealer didn't recommend changing the cabin filter yet, as it requires a lot of labor to get to. For me, the smell occurs mostly when I have the vent on. If I turn on the A/C, you don't notice it.

I have it too. Smells a bit like stale tobacco. Comes and goes.

here is the walk through http://legacygt.com/forums/showthread.php?t=64635