Steaming Windows

kullyb · January 7, 2013

Hi

Just bought an IS 220d SE-L but having problem with windows steaming up constantly. Any idea how to avoid this. I have turned a/c off to save fuel.

Any advice would be welcomed.

Thanks

steve2006 · January 7, 2013

Hello and welcome to the LOC.

I think you have answered your own question by turning the AC off, AC not only cools the car in summer but it helps remove moisture in the cabin in winter.

Leaving the window down slightly may help if you don't want the AC on and bear in mind most AC systems don't run constantly and will not operate below 5 degrees C so extra fuel useage will be minimised.

You could also check your pollen filter as this can affect good airflow if sufficiently clogged up.

The topic title brings back memories of my younger days :D

kullyb · January 7, 2013

Thanks a lot for the reply. is the pollen filter located behind the glove box?

Cheers

steve2006 · January 7, 2013

They are on other Lexus models, there is usually a clip off cover at the rear of the glovebox and the pollen filter tray is behind.

Just had a look at the exploded diagram and it looks like it is under the glovebox so look for a cover on the base.

kullyb · January 7, 2013

Brilliant. Thanks for that. will get it replaced weekend does smell a bit in the car so i assume it is this.

steve2006 · January 7, 2013

Also grab an aerosol can of AC cleaner, it removes bacteria and smell in the system. Just follow the instructions on the box.

CHUNKY CHIP · January 7, 2013

Steaming windows also can be other problems also related

wet floors?

boot floor wet?

water ingress?

heater matrix leaking?

just a thought

Geoffers · January 8, 2013

Yes, the filter is in the glove compartment behind the little shelf thingy that comes out. You will see the cover that just cips out. Be careful taking out the filter - male sure you are in recirc mode or you'll damage the damper arm when pulling out the filter.

Also, as Chunky says, check your footwells under the carpets. Mine were soaking and it turned out to be the condensation drain for the aircon clogged. This particular drain is right on the bottom of the unit though so meant the dash had to come out. I yours under warranty? If your floors are wet, get it in. I did read on another Lexus forum that there is a way to get to it from the underneath but can't remember where now.

kullyb · January 8, 2013

Hi Guys

Thanks for all the advice will definately check all these items outs.

Geoffers the car has a one year used car warranty. So will check out what it covers.

Thanks all once again.

Great forum site.

Kully

kullyb · January 8, 2013

Hi have checked the floors they are completely dry so i can rule out the condenstaion drain. Will replace filter weekend and do air con clean to get rid of smell,

Much that it may not be something too expensive.

Kully

juicestop · January 8, 2013

This is happening because you turned the A/C off. Run the car with it on, the windows will be nice and clear. The amount of fuel you will save is probably negligible having it turned off.

Shepherd · January 8, 2013

Yes, please keep AC turned on all time. It also makes the climate control work better imho. Most people leave it on all the time and I personally think the effect on fuel consumption is negligible.

CHUNKY CHIP · January 8, 2013

i run a/c all year when ever car runs it does not a warmy type i prefer -5 nice

oit keeps thing at a good all round temp and also as above controls a lot of the interior moisture

eg wet coats umbrellas even wet feet on carpets all cause steamy windows as todays cars are so tight sealed as they should be older cars never had problems they always had some form of air flow from points they should not have LOL

Ivanmtodorov · January 26, 2016

Hi guys,

I am new to this forum as this is my first Lexus. Mine is IS 250 SE 2007. Love the car to bits, but I had the same problem too after I changer the pollen filter.

I thought that the flap which stops the air coming in the cabin is jammed shut and that was the reason why this was happening, as it has happened to me before on a different car.

However, I opened up the glove box and decided to check first if I had put the filter in correctly. When I opened it i noticed that the lid of the filter box was opened, as soon as I closed it you could see the mist disappearing before my eyes, the intensity of the airflow also instantly increased when the lid was locked down. The catch which keeps the lid shut is a bit flimsy (at least on my car),so I think that's what caused it to open by itself. I don't drive with the AC on unless there is a need for it, which for me is just in the summer months. I had tried every other remedy prior to this, silica gel, demister pads etc but nothing worked. Hope this would help someone here, it's free and it takes 1 minute to do.

johnatg · January 26, 2016

You should use the aircon all the time. Apart from anything else, using it keeps the seals in good order - they dry out if it's not used. The lubrication oil in the gas is essential for keeping the seals working. Using aircon has no, or negligible effect on fuel consumption on these cars and it is designed to be on all the time. It doesn't affect the temperature in the car unless it's really hot outside (that is set by the climate control) and in winter you are warming up dry air rather than damp air.

The most important function of aircon is drying the air in the car, not providing cooling.

Verbout · January 26, 2016

I can't believe people don't have their climate control on all the time.

You're just fighting dampness in the car and condensation on the windows with it off.

As several have mentioned it make a negligible difference to the mpg and not using it will cause it to prematurely break.

And please be careful taking the pollen filter out, use the correct procedure.

toffee_pie · January 26, 2016

my AC is always on, as mentioned above be careful with the door cover on the pollen filter.

normski2 · January 27, 2016

Be very careful if you want to change that Cabin/Pollen filter. I've been meaning to put up a guide with pics for the 250 ... but in the meantime ... here's one that will work for the is250. The only difference is the removeable shelf looks a tad different. If you've set the recirculate button correctly the filter lid will be in the 'up' position with the filter in full view.

Credit to Connoisseur for the guide.

Ivanmtodorov · January 28, 2016

Hi guys,

thanks for the response and the info from normski2. I think that's where the problems stems from. I had a look at the service history and the filter was changed several time during the car's life. Probably the lid mechanism got damaged as a result. I will keep it close, as if you engage the recirculating mode it gets stuck in open position. Will keep the AC on and see what difference that would make overall, I wasn't keeping it off due to mpg concerns. If that was the case I wouldn't have bought an IS 250, but a Prius. Once again thank you for your advice.

jayt13 · January 28, 2016

I keep my switched off all the time and have no windows steaming issue i just keep the blower on set to footwell and windscreen, and set the temp to 21.5 degrees in the winter.

When it is raining the front window steams up sometimes then i put the AC but i switch off after a while cause it feels cold.

Linas.P · February 4, 2016

AC not only should be on All-Year round, but it actually must. Steaming windows are just a little problem in comparison with replacing whole AC unit as it gets damaged when unused for long time. That would cost up to £1000 (or 20+ years of average saving on fuel) to repair.

Have anyone actually have a figure what is MPG difference with AC on and off? I am sure that is like in a range of 0.1-0.5 MPG (there are some speculations that it could be up to 5%, but that is maybe for small engine and light cars, definitely not for relatively heavy IS.. I believe it woudl be far less than 1% from overall consumption) . Obviously, there are many things to suggest, but the easiest and cheapest as well would be simply... well turn on the AC!

Few examples:

You can buy sponges or containers which absorbs the humidity ~£7-19.
You can leave your car engine ON after driving and heat the car for 15 mins, then open the windows and doors to ventilate it and the remove humidity this way (you woudl spend like £0.50 each time on idle fuel consumption).
You can open windows when driving, but remember that in speeds excess of 40mph the air drag will consume more fuel than the AC.
Regularly disinfect your ventilation/AC ~ £20

as you can see there are options, but not only they going to cost you more, they will be more time consuming and inconvenient.

Let's assume the AC uses the whopping 0.5MPG - that would cost you a year maybe ~ £50 (in case of lexus this is surely going to be less). Buying several absorbing containers and constantly keeping you car well heated and ventilated, not only going to cost more, but as well going to be significantly more inconvenient. And all that assuming that your AC will not go wrong.

As well by not using your AC you are letting for germs to grow in the condensations tank and that not only stinks when you finally use your AC, but can as well cause severe diseases.