Audi A4 - Smell from air vents

[Bugeyeandy]

Any ideas with this one?

With the air con on all is fine and clean fresh air comes through the vents no problem.

With the ECON button pressed - Air Con off there is a strong stale smell of cats piss/wet dogs etc

I've run one of the those air con cleaning cans in the car which did leave the car smelling fresh and clean but as soon as the air con was turned off the foul smell came through the vents again.

I've also changed the pollen filter, the smell is definitely not coming from the seats or carpet and only comes through the vents.

Any suggestions of things I might check? I plan on taking out the glovebox and having a look at the fan in case something has died in there but i'm struggling to think how the airflow might be different with air con on or off.

[jr123]

I don't think it's just your car as iv also smelt it in an A4, that was a 2002 B6 tdi

[Bugeyeandy]

Mmm, thanks JR.

I'll do some googling see if theres anything common.

[Jack_and_MLE]

I have been told it's a good idea to run the aircon at max temp for a 10 minutes from time to time so to kill the bacteria inside the aircon.

I have done that and the smell is gone.

I'm also going to buy those can from halfords to clean system out

Jack

[Bugeyeandy]

Jack, I think you might just have fixed it for me.

I ran another one of the air con cleaning cans in the car but this time with it on max heat (last time I did it on full cold). I left it going as per the instructions on the can for a good 20 minutes and it seems to have done the trick.

It smells of nothing now regardless of what settings I have it set to.

Reading elsewhere it's bacteria on the air con condensor which gives off the smell, these canned cleaners kill of the bacteria apparently.

Chuffed to bits thanks Jack

[Bronze Stallion]

Hey,

I have exactly the same problem on my 2007 .TT - cat piss smell describes it perfectly! .....so if I read this correctly, you put the temperature to MAX HEAT with blower at MAX too? (no air con switched on) and directed downwards?

Thanks for your help.

[si_xsi]

I had the same with my old golf r32, changed the cabin filter under the glove box and it was filthy. Don't think they get done at services and different to a pollen filter.

[cuprabob]

si_xsi said:

I had the same with my old golf r32, changed the cabin filter under the glove box and it was filthy. Don't think they get done at services and different to a pollen filter.

Cabin filter and pollen are one and the same in a MK5 R32: and should be changed at least every 2 years / 20k miles.