Steam

[taxi3528]

Every time it rains the interior steams up when somebody damp gets into the car, a real pain in the backside as the demister struggles to keep the screen clear, I have even blocked off the rear foot well vents to try and divert more power to the front, 10% higher fuel consumption means that the air con is only used sparingly and when it is turned off it gets worse.

Anyone got any ideas how to solve the problem?

[M1tchy]

Check your pollen filter and air filters aren't wet and change them if they are. Also try some anti fog stuff from halfords.

[kite]

Scan for faults, sounds like you have a air distribution flap stuck.
Your HVAC could be stuck in re-circulation mode.
Also check your front passenger footwell for damp..

[Quatrelle]

"the air con is only used sparingly and when it is turned off it gets worse"

Indirectly you've answered your own question. Check what the others have suggested, and leaving the aircon on all the time will probably cure the problem.

I'd be interested to know where you got the 10% increase in fuel consumption from - that's more than I've ever heard. My aircon is never turned off, the extra fuel used is a small price to pay for keeping its seals intact and the glass clear.

[M1tchy]

As above, missed that bit first time. Where did you get 10% from? Put it on and won't have any probs, but I also use anti fog and ensure the filters are dry.

[taxi3528]

The 10% increase is when trundling around town but it's not so bad out on the open road, the pollen filter was renewed recently but I will have a look to see if it's wet, never tried the anti fog stuff but will do so soon, don't think it's stuck in the recirculation mode but will start checking tomorrow.

[MDA123]

I have tried that anti-fog stuff from Halfords and wished I hadn't: it left a smeary mess which still fogged up (it was a couple of winters ago) and I had to get a shammy to clear it off. I think a well rinsed shammy used on a warm or sunny day is probably the best way to clean the inside of the windscreen - whatever glass cleaner I've used always seem to leave a residue that is either smeary or fogs up even quicker.

As regards using the air-con, yes it will quickly clear the screen but you then have to leave it on. If you switch it off when it is still raining then the moisture on the condenser will instantly fog up the windscreen and is much worse than if the air-con had not been used in the first place. You pays your money and takes your choice.... I guess that as long as you use the air-con from time to time the seals etc should be okay but I don't like it on when driving in town as you can feel the reduction in engine power. I've put on those side window deflectors and drive with the windows slightly open so any rear seat passengers shouldn't get wet!

[vespa]

Use the aircon and keep the car clear is the only answer. The magic potions will, as mentioned, mess up the glass. OR as an alternative put your wet passengers in the boot!:biglaugh:

[Quatrelle]

One thing that makes the windows steam up quickly is dirt and, in the case of the windscreen, the deposit of crud that comes off the plastic vents and piping, and traffic fumes (diesel etc.) that get blown onto it by the fan. If a proprietary domestic glass cleaner doesn't work for you - it always does for me, but your car gets used a lot more than mine so you might have to do it a couple of times - use neat alcohol or methylated spirits.

Failing that, you could always try windscreen washer fluid - works on the outside so perhaps on the inside.

[MDA123]

Use the aircon and keep the car clear is the only answer. The magic potions will, as mentioned, mess up the glass. OR as an alternative put your wet passengers in the boot!:biglaugh:

Or better still, just tell them to stop breathing!

[Teflon]

Aircon on, bag of desicant on the back seat, drive naked and don't breath. Either that, or move to North Africa.

.