Air con still smells even after air-con service

[Monsoon]

Please help!

Last summer my air con started smelling. Over the winter it went away. It was back again at the start of this summer so got Hitchin Audi to do an air con service (they actually did the desanitising process twice so I know it's been thoroughly cleaned out). But just three weeks later, the smell has come back.

Here are the exact symptoms:
- The smell is there when I first start the car and interior fans begin to blow (whether with air con on or in "econ" mode). After a minute or so the smell usually goes away, though occasionally I will get a slight whiff half way into a journey.
- If I stop the car/fans then restart within an hour or so then there is no smell. It is only noticeable on start up after the car has been resting for at least a couple of hours. It seems like the longer it's been resting, the worse the smell.
- The smell is difficult to describe - nothing like what others have described (e.g. musty, BO, mouldy cheese, cats pee, eggs, etc). The closest I can think of is a pungent pollen smell - as though you're walking through a field of oil seed rape, or flowers which are well past their best and beginning to decay. It's quite unpleasant.

I've had the pollen filter changed so it's not that. Any ideas gratefully received!

Thanks.

 

[Monsoon]

Oh. Forgot to say that I've tried my own desanitising spray can in the past too - no success. And often run the air con maximum hot/cold as recommended to clear out the system - again no success.

 

[mark a4 tdi]

have you changed the pollen filter under the bonnet passenger side next to the battery. as i had same problem an that sorted it.

 

[Monsoon]

I thought the pollen filter in the 8p chassis was accesible from the driver's footwell. I know in the previous generation A3 it was only accesible from under the bonnet. The pollen filter under the driver's footwell was changed two months ago. Is there another pollen filter under the bonnet then?

 

[bamurphy]

Ive just changed my pollen filter today in my 8P A3, and can defiantly say that it is in the Passenger foot well. The 'Pollen Filter' refered to in the engine bay near the battery is the 'Air Filter' for the Engine.

 

[Monsoon]

Yes, sorry, that's what I meant - the passenger footwell, not drivers. I don't suppose changing the air filter would make any difference would it?

 

[PW-Motorsport]

Some garages just spray in some cheap smelly stuff. You need some proper anti-bacterial product, such a Wurth or similar.

This is sprayed directly into the aircon air box via water drain hole. It is a strong solvent based cleaner, so ventilate the car before you drive it.

 

[JimC64]

Some garages just spray in some cheap smelly stuff. You need some proper anti-bacterial product, such a Wurth or similar.

This is sprayed directly into the aircon air box via water drain hole. It is a strong solvent based cleaner, so ventilate the car before you drive it.

Good advice from PW......I've seen a smilar thread where someone used a dettol disinfectant spray / Zoflora or similar, as per the above instructions twice over a couple of weeks and it really helped to cure the problem.
The other advice is to use your air con " very often" I tend to use mine 90% of the time as this helps to prevent the build up of bacteria within the system.

Good luck and please let us know how you get on

Jim

 

[Monsoon]

Some garages just spray in some cheap smelly stuff. You need some proper anti-bacterial product, such a Wurth or similar.

This is sprayed directly into the aircon air box via water drain hole. It is a strong solvent based cleaner, so ventilate the car before you drive it.

Where is the aircon air box located? And the drain hole location?

Thanks.

 

[JohnboyC]

Ditto Monsoon "Where is the aircon air box located? And the drain hole location?" in my 2003 A4 Avant 2.5 TDi Q Sport

 

[PW-Motorsport]

You should see a drain in the bulkhead engine bay side.

You will notice the water coming out from this when the aircon is switched off.

 

[Monsoon]

Try as I might I can't locate the drain hole. Had the car jacked up and everything. There are two points where I notice water trickling out - but these are from the droplets of condensation that form along the whole length of air con pipes.

 

[SixDegrees]

You should see a drain in the bulkhead engine bay side.

You will notice the water coming out from this when the aircon is switched off.

Annotaed pic please?

I have a funny smell, a bit engine bay chemical type smell, not exhaust or oil but certainly not bacterial. I've no leaks or the like in the engine, g/box, etc that would allow liquids to accumulate in that area and then be sucked up into the AC so I'm assuming its the AC

AC blows very cold / hot when required so I think the AC has been serviced recently, although car had been lying for year before I bought.

SWo, would like to be able to check this out in mroe detail and do some sort of home service on it.