jharrod

Anyone else get a moldy smell from their AC when you start your 997? I had mine in once and they said that the cabin air filter had some mold on it and they replaced it. The smell went away for a couple of weeks but it's back, and this time the filter is clean. The service manager's story is that I should expect that unless I'm running the fan with the AC off for a few minutes every time I shut the car down to clear up any condensation, which would seem like a reasonable answer if I had never been inside another car in my life.

So as I see it the possibilities are that the 997 AC is uniquely poorly designed and is trapping and failing to drain moisture, or there is a problem with my car in particular that's letting moisture get where it shouldn't be, or maybe at some point there was a one-time event that let mold grow on the filter and it spread enough that just replacing that element didn't take care of it.

Any thoughts or similar experiences?

Paul Marangoni

My girlfriend's BMW 3 has a similar problem. In her case, I think it's because she hardly ever uses the AC. Do you use yours regularly? Mine is always on, and I have never experienced any odd odour. Do you use your car everyday or does it sit idle for long periods?

jharrod

My car is my daily driver and the AC is in use every day.

MMD

The pollen filter (cabin air filter) still lets organic matter thru it. (I think even HEPA filters won't take out all organics). Mildew needs very little organic stuff to grow. It's a crap shoot if you get the right conditions for the myriad species of mildew to grow. It will grow anywhere. (even grew on a camera lens left on the Moon!).

My thought is that you must always follow the "run-fan-with-ac-off" procedure every time. I do this with every car I own, when I get to the stop sign at the end of my street I shut the AC down. Never had any smells again.

Just a guess on my part. Perhaps you've a malfunction. You can also safely spray Lysol into the intake vent to get nasty with it.

texas911

Don't use recirculate! It causes mold to grow on your coils. Happens to all cars, not just Porsches. If you read the manual on any new car, they don't recommend using recirculate continuosly.

MMD

THAT would makes partial sense because you're adding organic matter from inside the car to the coils that hasn't been filtered.

I say "partial" since, once you've "fertilized" the coils by using the recirc button once they stay fertilized for a long time, right? Just using the recirc button for a few hours on a new car permanently contaminates the coils, huh?

You're also depending on the AC to do MORE dehumidification when recirc button is on. So interior coils are getting SOAKED.

BTW, I use the recirc button 90 percent of the time on every car I drive.

So, it looks like all you can do is attempt to control the moisture left sitting in the parked car, by running the fan w/o AC.

SrfCity

I seem to recall that there is something you can spray into the incoming vents to get rid of the odor. It might be Fabreeze? Something that would kill mold might do the trick too. Google it and see if you find anything. Let us know?

holminator

Lysol. Spray it in the outside cabin intake with the fan on full for 30-60 seconds. That should kill it.

The_Phantom

Instead of lysol use Wurth A/C & Heating System Cleaner. Here's a link to its description at autopia.com

http://store.yahoo.com/autopia/wus-893540.html

SrfCity

Thanks for the link that looks wurth it Lysol is a cheaper way to go though.

Michael1

I'm not sure I would want any chemical coating my A/C evaporator coils. Every car I have ever owned has developed "the smell". What I have found works for me lately, is on days that are not hot, but dry, just turn the A/C compressor off, and let the entire system thoroughly dry out. A few consecutive days without A/C, every few weeks, keeps the smell at bay.

Michael

djantlive

Maybe your evaporator is clogged with crap and needs to be chemically cleaned.

I'd try that AC cleaner or have a AC specialist inspect the cause.

MMD

Here's an experiment for you.

Wet a towel, put in plastic bag, put in dark closet, come back in a day or so: smell the mildew.

Then to the same thing with a dry towel and you won't smell mildew.

Conclusion: make sure the AC is dry before you park the car.

gradyex

MMD is correct. Mildew MUST have moisture to survive. You can use all the sprays you want and they will work temporarily at best. Being a painting contractor I come across mildew problems in bathrooms regularly and adding additional mildewside to paint works to prolong reoccurances but does not insure that it will return. Trust me unless your bathroom is properly VENTILATED mildew always rears its ugly head down the road. So leaving a window open + running a fan during and after showering is the ONLY solution to preventing its reoccurance. Apply the same thought process to your car and it will work. Its not as straight forward as a bathroom but get as much moisture out as possible before turning that key off. I'm sure humidity in the air plays a big role here as well as temperature factors. The closer to the equator you drive your car in the tougher it is getting rid of that fungus/bacteria that had millions of years of evolution to survive the hardest conditions and it will always win unless you make its environment "unlivable".

texas911

Heres the deal if you have recirculate on all the time there won't be a place for the moisture to escape. So don't leave your A/C on recirculate on all the time. Simple.