Misty windows Porsche 993

[Watson]

Hi guys,

Normaly I write about my 911T and my 912, but this time it's about my 993.

My windows is fogging/misting up on the inside. I had the problem before I put it in the garage for the winter. I hoped I could solve the problem this winter. Here's what I've done:

- Airconfluid checked and refilled.
- Cabin air filters changed.
- Airbox drains checked.
- Sunroof drains checked
- All door seals are new, and there ar no wet carpets anywhere.

This winter it was standing inside a dry Garage in 20 degrees celcius.

After 5 minutes of driving (in dry, cold, but sunny weather) the windows was fogging again.


Have you any experience? What can the problem be?

Thanks guys

[petric]

993 have a thick sponge under the carpets they are probably wet they can leak a lot if the sunroof drainpipes have come disconnected (if you have one fitted) and the pollen filters can be a problem but you say you have changed them ?

[mycar]

Stick a dehumidifier in the car for a couple of days.

[Watson]

There's no water in the bottom of the car, and the drain pipes from the sunroof is doing their job.

The only thing I can think of, is the aircon system or the heat channels from underneath the engine. I'm thinking something is wrong, but I can't figure out what it is.

I won't use a dehumidifier in a dry car. If there's moist, the aircon should do that job. I would rather find the root to the problem.

[mycar]

Is this something that only occurs when you are in the car ?

[KS]

Is this something that only occurs when you are in the car ?

He could try driving for an hour or so without breathing, just to check if that's the problem. Waddya reckon?

[Bruce M]

Did u leave the windows open over winter?

See if you can borrow a moisture meter and take readings from the carpet.

[mycar]

Kill or cure Keith ? I like your thinking but perhaps a little drastic this early in the investigation.

Watson, we need to iliminate the impossible... and then whatever remains, however improbable, must be the truth.

I think Keith is only joking about the no breathing. Seriously, you need a sauna suit and rule yourself out of the equation.

[Watson]

Ha ha! I try not to breath in the future... I'm crazy about that sauna suit. It would look good on me, while driving in a matching silver Porsche

Well... Seriously. I made some test drives with aircon on, aircon off.

"Aircon on" is the sinner... I dont know why. It should be exact the opposite?! The aircon should dry out the air?!

[scalino65]

Watson, we need to iliminate the impossible... and then whatever remains, however improbable, must be the truth.

hahahaha good one! Its elementary, my dear....

[dean1057]

Has the air con dryer unit ever been changed? they do absorb the moisture in the cabin when you have aircon on even with the heating on.
http://www.porscheshop.co.uk/acatalog/a ... g_993.html

[Watson]

Thanks Dean,

I don't know if someone ever changed it. All Maintenance history is in Japanese.

When I reed the Internet about what the dryer should do, I think it's a VERY good idea to try to change it. Thanks for your input!

I will order it right away, and I will get back as soon as it's changed

[Bruce M]

The dryer removes moisture from the air con gas circuit. The air con refrigerant absorbs water which stops it working effectively, a full vacuum of the gas circuit & refill often sorts this out but the dryer can get old and need replacing.

If the air con isn't actually cooling the air properly, it won't dry the air and it needs a service.

[KS]

I think Keith is only joking about the no breathing. Seriously, you need a sauna suit and rule yourself out of the equation.

No, I wasn't joking...
If I were you, I'd try that sauna suit along with a plastic bag over the head – or ask to borrow one of Bootsy's latex all-enclosing gimp suits...



Before that, change the drier and give that a try...

[Jonny Hart]

The dryer removes moisture from the air con gas circuit. The air con refrigerant absorbs water which stops it working effectively, a full vacuum of the gas circuit & refill often sorts this out but the dryer can get old and need replacing.

If the air con isn't actually cooling the air properly, it won't dry the air and it needs a service.

^ Correct and correct.

I have our prototype new air con in my SC and it defogs almost instantly. I suspect the air con isn't working. Check the temperatures at the vents.

On the 964/993 there is a servo that operates the recirculation by shutting off the scuttle air intake. If this isn't working, the air con might struggle to defog really humid air. But, TBH, it's more likely the system isn't working.