rev up your engines, today I'm going to show you how to keep your car windows
from fogging up, car windows fog up because water condenses on them, now this
can happen both on the inside and the outside of your windows, water condenses
on the surface when the temperature of the surface is below the dew point of the air
that's near that surface, we're doing weather reports now, when you have warmer
humid air next to a cooler glass, it's gonna condense and create fog on the
window, now having condensation on the outside of your glass is no big deal
that's what the wiper blades are, they just wipe them off, it's the fog on the
inside that you want to get rid of, now the easiest way to get rid of is to put
your car on defrost, full blast, with the heat turned on as
high as it goes, you can see it's gone already now but when you do this, you want to
make sure that your air system is on fresh air and not recirculate, because if
you have it on recirculate, then your recirculating all the air inside the
vehicle and not get any outside air, now that's a bad thing when people are
sitting inside the car, because we breathe out a lot of water vapor and
that's gonna make the dewpoint change because it's going to make it more humid
and it will fog up even worse, so when you want to prevent any fog or get rid
of fog that's there, you want to have it on fresh air, as hot as you can turn it,
and full-blast to have the drier air and warmer air blow all over to keep the
windows from fogging up, now many modern cars prevent things from fogging
up automatically because when you put the defroster on, many of them turn the
air-conditioning compressor on, now that might sound counterintuitive that you
got the heat on, but then the air-conditioning is coming on too, but
there's a big reason for that, yes the hot air is hot, and it'll keep the glass
from being cold and condensing water on it, but air conditioning air is
extremely dry, so if you have a combination of your heat and your air
conditioning on you're going to have hot, dry air blowing
inside the vehicle so the windows aren't gonna fog up, and I know some people are
gonna think, well Scotty I'll be freezing to death in the winter if I have the air
conditioning on, well no because air conditioning is much weaker than heat, if
you combine the heat of your car's heater with air conditioned air, it's
still gonna be really warm, so as nutty as it sounds, if your car is fogging up
more than usual in the winter, check your air conditioning compressor to see if
it's still working look down at the compressor and if you
see the front of it spinning, that means that the compressors turning on and it's
working, if it doesn't come on at all now you can see the front isn't spinning,
you'll know the air conditioning compressor isn't working and giving you
dry air, know there are products out there like this rain-x anti fog, they claim
they'll prevent fogging up in a vehicle but I found they don't really work all
that well, one you got to keep applying them over and over again, and if you read
the warning labels, it says do not use this product on painted services, non
clear surfaces, surfaces treated within anti reflective, scratch resistant, or
other coatings, and soon many cars are coated this day you know what the coating to
come off because you sprayed stuff on it when I was younger I did a lot of scuba
dive, and we didn't want our masks to fog up, what we did in those days was, we rinse
the mask with water then we spit on the mask and wipe it through as a
little coating, but you had to do this over and over again and really do you want to
do that in your car, but there is a way to make the possibility of fog as little
as possible, use a really good cleaner these handy little blue shop towels I've
been using them for decades, because just like rain clouds, fog needs things to
condense upon, if you get all the dirt off of it,
there's less of a surface area for any of the moisture to cling to,
I like these Scott shop towels, cuz I've been using them a long time, they're strong
but they're also soft, they're not gonna scratch anything, and the stoner
invisible glass it's great for cleaning windows, it doesn't leave streaks and it
keeps them nice and clean and who wants dirty windows anyway, realize
clean windows hey that's the best defense you can have against things
fogging up or smearing up, cuz this anti fog stuff, it even says it's an eye
irritant, well I tried to stuff out in my wife's Lexus and guess what, she's pretty
sensitive to chemicals and stuff and it irritated her eyes and her lungs too, I
had to clean the whole car off take all the stuff off, so if you're really
sensitive don't even think of trying this stuff in the first place, even I
found that to be true ages ago and I did a lot of scuba diving,
they had anti fog sprays that you could put on the inside of the mask, but they
irritated my eyes and man I'll tell you I'm not usually bothered by stuff too much
but, it made them tearing water up and I had to stop even using that stuff, so now
you know how to keep the fog at bay inside your car and since this mechanic
Monday I'm giving away some of the stone or glass cleaner and these blue shop
towels, to have a chance to win put a clean non offensive comment on youtube
comments below and their winner will be chosen randomly by computer to have a
fog free car, so if you never want to miss another one of my new car repair
videos, remember to ring that Bell!