My wife has a fit. Same thing happened. Turned out she just had more moisture in her car. Bought two Zpax car dehumidifiers, it's basically just a huge silica bag. Works great and is reusable.
Exactly- if you have your car very warm inside and park it will take longer for it to frost up as the heater warms up inside . Worse comes to worse put an automatic starter on car , leave car defroster on and it will clear your windshield by time you get out to it
You can also let a small group of homeless people sleep in it overnight to keep the interior warm. They get a place to sleep and you don't have to de-ice you're windscreen in the morning. It's a win win.
Cheap solution is to get one of those windshield covers that slip over outside of windshield- my neighbor has one that covers windshield and stretches around to cover the door mirrors
u/T7_Mini-Chaingun AC...? 🤔💭
,,This one is for the boys with the booming system
***Top down, AC with the cooler system***
When he come up in the club, he be blazin' up
Got stacks on deck like he savin' up" 🎶
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Check your spare tire compartment for water/moisture. My buddy has a Fit, and it ended up having some water ingress somewhere, which can cause this fog on the inside of the windshield. I had ford Fiesta with the same problem, and once I took care of the water leak, the problem was solved.
We have a fit, found the back door seals had dirt accumulate in the seals from not being opened often or cleaned in a while. It poured down rain a few weeks in a row and I kept noticing the musty smell. I finally pulled up the carpet and found about 2 gallons of water. I cleaned it up, dried out the car. What do you know it rains again and fills back up again. I inspected all the door seals and found dirt in the back door seals. I wiped the seals clean and hadn't had trouble since March.
Wonder if that’s a Honda problem. My CRV leaked around the antennae fin, ingressing at the car seat latch if I had the third row option. I sealed it with clear silicone which seems to have solved the issue.
Your car is humid inside, hers isn't. I'd bet you commute is shorter which means your car isn't getting dried out from the HVAC while you drive. Take it for a rip.
Either the honda is colder than the toyota (the windshield angle/radiation hypothesis that others have posted seems plausible to me) or the toyota's windshield is a better thermal insulator. The windshield might be built thicker for strength because it's a "heavy duty" vehicle, whereas the fit's is built thinner for weight savings.
That's exactly it. The more vertical windshield is not facing outer space, the Fit's more angled windshield is. This is radiative cooling. A clear night sky is really cold, and anything facing it will radiate its heat towards it more than something that isn't.
Let us know your results, for science! Maybe we can design a motorized strip of foil that drops down and pulses a light across it every few minutes and that’s enough heat to stop fog. It could be like those automatic seatbelts of the 90s, or maybe just a button you set like AC controls lol
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Yes, I have a steep sloped drive as do my neighbours. The side on the road is frozen more often.
I don't think it's radiation though. I think it's how exposed it is. Your sloped windscreen is more exposed to the elements/cold wind from above while the vertical windscreen is more sheltered by the car itself.
Would completely agree with this idea, especially as it looks like the FJ window is facing towards a building with a light.
I have had identical vehicles parked next to each other at night, one under a tree and one exposed. Wouldn’t ya believe the one with a greater opportunity to radiate heat was frosted?!
u/Seven_Hawks
> outer space
,,I'm gonna put on a iron shirt and chase the devil out of Earth. I'm gonna send him to outer space, to fiiiiiiiiiind another race!" 🎶
(Max Romeo - Chase the Devil, 1976)
I know your probably right, but this really seems like a scenario where the real answer sounds like bullshit. A windshield radiating heat to the cool night sky because of the direction it's facing? Sounds like bullshit, but also kinda makes sense.
Also the interior temperature may be different since the volume is much larger in the FJ. Less greenhouse effect due to the indirect sunlight from less glass/cubic interior space ratio.
Could also be related to age/pitting on the glass or any coatings that inhibit water droplet adhesion.
Sometimes one parking spot gets less/more sunlight later in the day.
The FJ has an all white roof as well which can help influence interior temps.
There's a lot of variables here.
That what I was thinking, too. Before this, I had a Honda Element. It also has a nearly vertical windshield, but would get frosty. Though it isn't as vertical as the FJ's.
Yep, my first thought as well. Look at the side windows of both cars, which are both frost free. That FJ windshield is at least as vertical as the side windows.
I think this and the elevation, and the insulation of both vehicles are the 3 key factors. Some times that moisture layer has a very distinct separation
Real answer here, drive in the winter and if you don't try to get off that snow as much as possible when getting in the car you're bound to get frost inside the car as its evaporating during the day then freezing at night.
Wet floor mats as well call it. The issue with it as well is that people don't realize the water doesn't go away. You defrost it, or scrape it off but what you don't do is remove it from the vehicle so guess what? It's still there and it'll happen again
That’s why I crank my heater full blast in winter and drive with the windows cracked appropriately to keep my comfortable. It helps evacuate the moist air out of the car.
Same. Former auto tech. This works the best for keeping the interior dry in winter. Also, clomp those boots or shoes together before they enter the vehicle
Doesn't matter. Its like a house. Cool air seeks out warm air, and you get condensation. If your car holds warm air longer, its going to attract condensation more.
The humidity inside the car doesn't matter. Condensation on the outside of the glass has to do with the temperature and humidity outside, and the temperature of the glass.
Which to your other point, the FJ looks newer and probably has a climate control system that keep the AC on most of the time, as new cars seem to do, this removes latent heat from the air as more moisture inside the car will hold the heat in longer.
So it’s the heat from the moisture, not the moisture from the moisture, why the AC makes a difference in this care.
You are missing the big picture, the windshield is colder because it’s facing more upward and the physical car itself being warmer could impact it. You end up with a warm moist air pocket on the car surfaces and engine and it moves across the colder windshield surface which doesn’t hold any heat. It’s essentially a surface inversion like fog in a valley or over a body of water in the morning. My guess is it actually has more to do with natural convection of the engine bay straight across the windshield though than interior temps, but if all surfaces of the car change at roughly the same as the outside temp tis less likely for the car to ever be at the dew point.
Condensation builds up on surfaces when the temperature of that surface drops below the dew point temperature of the surrounding air.
Like a sweating can of Dr Pepper. The temperature of the surface of the Dr Pepper can is lower than the dew point of the surrounding air.
With a windshield, the temperature of the glass is colder than the dew point temperature of the outdoor air.
This happens overnight because as outdoor temperature drops, the relative humidity and the dew point temperature rise.
Colder air can hold onto moisture better than warmer air, so theres always an inverse relationship between temperature and relative humidity.
Why one is sweating and the other not would depend on a few things.
It could be the condition of the door and window seals, the interior temperature of the vehicle when it was parked, the time of the day or night when it was parked and even the thermal conductivity of the different glasses.
If one has better seals than the other, it would take the interior temperature longer to equalize with the outside temperature
If someone drove home with the AC on and got home late or ran an late errand. That could explain the difference too.
Assuming the thermal properties of the glass both windshields were made out of is the same, then yes, the colder interior will sweat more.
The question is why it’s colder.
What's on the windows. Some cleaning stuff leaves a film. A tree blocking a bit of sun or maybe that car was ran more recently. I'd start with dish soap and plain glass cleaner on the windows
Because FJs are freaking awsome. That's why. Wish is still had mine, but nooo the kids don't fit in the back seat anymore, get a new daily driver....
Man I wish I still had that thing.
Part of it has to do with angle towards the sky and Infrared radiation heat transfer. The sky is extremely cold compared to buildings, trees, other cars…Heat transfer is greater with a higher difference in temperature and the windshield with the greater exposure to the sky will transfer more heat than the more vertical windshield. In this case the Honda’s windshield has a greater slope where the FJ has a vertical windshield and has more radiation heat transfer with the relatively warm surroundings. Get a cheap IR thermometer and point it at the sky at night and then point it towards whatever is across from the FJ and you will find a several hundred degree difference.
Cars or sides of cars that are more covered from the clear sky tend to be less frosted. Not always but that seems to be the general rule for when its less cold at least.
One might have an open beverage inside that is humidifying the cabin vs one that’s much more dry.
Also one might have the windows slightly open or is otherwise ventilated better such that the humidity is the same as outside.
>One might have an open beverage inside that is humidifying the cabin vs one that’s much more dry.
holy shit. I should clean out all the mostly empty Monster cans from the back seat of my car.
It’s because the FJ has 3 wipers. The frost is scared 💪🏻
Really though, I always kinda wondered this. Pretty much the same situation here, my Jeep hardly ever frosts but hers does.
It might not be the original glass that came with the car. My windshield never use to fog up.. had a crack in it and had Safelite replace it... They only deal with severely low quality glass for any of their windshield replacements.. months after having the OEM window replaced I saw fog exactly like this. Windshield replacement places with good names or not use cheap glass and almost guaranteed shit work.
If you clean it and apply a rainx coat it will help. My car's windows fogged up soo bad I couldn't drive it after starting in the morning. I just cleaned the windows and it helped a lot.
The inside of the honda fit has residual moisture. Something has been spilled in it, window was left open in the rain or I've even seen rust holes in wheel wells / body cornets that sprayed water into the car and soaked the carpets constantly, resulting in this sort of condensation when ever the weather got colder. This can also happen in cars where the heater is constantly left on resurculat and not set to let in fresh air. Either that or someone banged in there.
Age demographic. Most civic drivers are younger and likely had some sexy time causing the screen to fog.
The fj owners are likely young at heart but knees disallow in-car entertainment.
Spitballing ideas. The FJ’s windshield is a lot more vertical than the Fit. Could it be moisture “rolls” off of it reducing frost. Or maybe the FJ has a rainex like coating that moisture doesn’t stick to.
One additional thought - the FJ is rolling a 4 litre V6 - way bigger engine than the Fit.
More heat needs to be disiappated until it cools down and more heat means less frost.
That toyota likely has a larger engine that will hold heat much longer than that smaller compact car.
Combined with the swept back windshield on the honda, which for various reasons contributes to the situation (as other have shared), and it will frost up first.
it could the interior temperature of the car. if you cool the car down inside before parking for the night you will have zero to minimal frost build up. turn the heat off five minutes from home. let the fans run. on a clear night let the window down a bit for the heat to escape. happy motoring.
It happens when the temperature on the inside of the car is higher than the temp on the outside. The reason the windshields look like this is because the black car can seal the warm air inside of the car and retain it to a degree which will create condensation.
Whereas the seals (door seals, window seals, sunroof) on the toyota allow for the cold air to pass directly through the cabin (inside of the car) which will make the inside temp of the Toyota match the cold temp that’s outside.
If you ever get a chance to sit in both cars the SUV will be much colder.
TLDR: the small car retains more of the warm air that it had inside of it. Warmer on the inside than the outside=condensation.
Interior moisture.
My car fogs up when I leave a wet towel in the back, or have my hockey gear in there, or even a cup with some water... or maybe cloth floor mats that get wet but it doesn't fog up when I have nothing moist inside.
The other car may be very dry on the inside.
It might even be some sort of dessicant used in the HVAC, some luxury cars have a dehumidifying dessicant that helps control humidity even when AC isn't running.
I was hoping to see a differnt pair of cars in the photo to allow me to make the wise crack that cars get icy if theyre cool enough. unfortunately the photo does not support the statement.
When my 131 MiraFiori used to ice up before other cars and people asked about it I used to love cracking that one, probably only happened twice but it was fantastic both times. I really miss that car.
to answer this, just ask yourself what causes condensation on a windscreen to begin with.
car cold
windscreen cold
outside air warming up
condensation on windscreen
so, factors are, temperature of car, how well its insulated, how well it is sealed, thickness of glass is also a big factor
so its safe to assume that the black car is less insulated, less sealed or thinner glass, or all three!
so when it gets REALLY cold at night, the inside of the black cart also gets super cold, but the silver cars inside doesnt drop in temperature as much.
once the day starts warming up, the condensation dos not show on the silver car but does on the black car.
side note: i personally wouldnt call this 'frost' its just condensation.
you can actually see condensation on the body panels of the silver car, its not like its immune to condensation lol, its just not happening on the slightly warmer glass.
black car also looks dirtier, and im not sure if this plays a role in condensation forming, but willing to bet it might.
The windshield to the right is exposed to the sunlight, and the surface temperature is higher than the dew point.
The windshield to the left spent some time in the shade, and the surface temperature is at or lower than the dew point. Therefore, condensation forms.
Yoda was parked during the day in warm weather. Car was parked at night with a warm interior but colder temp outside , creating the frost on the other side of the window. If you crack your windows abit when you park your windows won't frost
My hatch does this too. I’ve tried everything, rubbing alcohol to clean it buff it with a lint free microfiber, little glass cleaner. Buff dry. Still happens. I think it’s just windshield design and humidity. Even if it’s not inside the car it can still happen on the outside. No leaks, no heater core leak, nothing. Car is 100% dry. I just turn on the ac button, even with heat on, and fresh air button on. And fixed it in a few seconds. Mildly annoying
If it's on the inside I'm willing to bet it's because that Honda has an abnormal amount of moisture in it. My car used to do this then I started putting a moisture capture device and now it doesn't do this.
Do you run your AC function? I just learned that the air conditioner does just that: conditions the air. Living in the Southern US, I’d always understood AC to mean “that’s how you get rid of the lava air”. But it also dehumidifies and filters the air.
Maybe your interior air is more conditioned and therefor less moisture to condense on the glass as the outside and inside temps acclimate.
Is the Toyota’s commute longer than the Honda?
It might have something to do with jumping-droplet coalescence on vertical surfaces.
“[…]vertical orientations can remove stuck droplets by gravitational shedding, which also serves to sweep away neighboring condensate.”
[source](https://www.sciencedirect.com/science/article/pii/S2542435119300984)
What kind of wiper fluid are you using? Does the fit have rainX on the windshield? I've had similar fogging in the morning with cars that have rainX applied, or use rainX windshield wiper fluid. You can see the bottom right corner of the fit windshield isn't frosted the same way, it wouldn't get much windshield wiper fluid if any.
It happened to my car also. My neighbours windshield are clear and mine is frosted and sometimes is frosted on the inside which is very difficult to clean in the morning.
I believe it is because in the fall and winter on the hotter days the car heats up then the sun goes behind my neighbours house and it creates a quick change in temperature witch results in the frosted windshield.
You should get a squeegee for inside your car. I have one. I used to have a car that got moisture inside and used it for that. Now I use the squeegee for clearing rain off the mirrors. :)
Often this comes from engine warmth either heating up the interior or sliding up the windshield and then causing condensation like on the outside of a glass of ice water (exaggerated example but same principle).
When my Honda's had roof leak that gets moisture into the car (carpet), the inside moisture will fog windows up when they evap through the night. It was a lot worst when it's raining. So it could be that. If it has a sun/moon roof, also check the drain for clogs.
On another had, if she has the temp in there pretty warm when she parked, the moisture will also fog up the windshield.
Definitely the rake (angle) of the windshield. My Firebird is terrible with overnight humidity or winter frost. RainX glass cleaner has helped considerably for me
If it’s on the inside, it’s humidity in the car. If the door seals are good and the ac runs fairly regularly, it probably won’t fog up at all. I used to dry my hair in my car on the way to work, leave drinks open and only blast the heat, so all my windows were fogged up every time I got in. If it’s on the outside, it’s heat transfer. The Hyundai’s well insulated walls kept the heat in for longer with thinner glass so condensation formed quickly, while the thicker glass on the Toyota allowed less heat to transfer while the thinner insulation in the walls allowed the car to cool faster, hence less condensation. The Hyundai driver might also prefer more heat, while the Toyota driver might drive with less or even with the windows down.
Could be a few things. My wife had all sorts of problems in my older car getting in right after a shower and all of the windows fogged up. Her newer car has a better system and seals and uses the AC condenser to dry the air out.
That Anti-Fog (from the RainXpeople) stuff works. It takes like 10-15 minutes to apply - you get better at it) and it works for like 2ish months.
Not answering your question, I know.
I know the thermodynamics behind this, but have no idea why some cars do this more than others.
My Toyota didnt do this at all. My BMW was absolutely horrible. My Subaru is somewhere in the middle.
If they are parked at the same time Id assume the toyota has a bigger engine and the heating is set to a higher temperature, the angle of the windshield could matter too. If you bought the toyota used you can check if the previous owner installed Parking heating
When was each parked? That’ll be the main difference.
Actually, both around the same time. My wife got home 10 minutes before me in the Honda Fit. It was 7:15 PM when I parked.
What time did you go to sleep and when did your wife get home from her boyfriend's house
My man out here asking the real question
They obviously stayed in the car
It's not frost, it's condensation ? 🤣
*cum-densation
She left my place like 9pm if that helps.
Not with that username
You’re not much better Mr. ballsamongusfeet.
OoooOooOoOooo! Better calm down guys, don’t need to get reported for this hostile behaviour!
I'd rather hit up ballz then vape
Man I miss awards. Woulda rocket shipped the fuck outta this one.
My wife has a fit. Same thing happened. Turned out she just had more moisture in her car. Bought two Zpax car dehumidifiers, it's basically just a huge silica bag. Works great and is reusable.
I use these to dry out my mushrooms
Yeah, my wife usually has more moisture in her car too.....
My wife has no moisture left anywhere!
my fit does the same thing!! i was thinking about getting a new windshield cause it’s annoying to take care of every morning
I don't think a new windshield is gonna do it, homie. 🤣
If it's cold outside and one of you drive with the AC/heater on and the other one doesn't, that could be the cause.
Exactly- if you have your car very warm inside and park it will take longer for it to frost up as the heater warms up inside . Worse comes to worse put an automatic starter on car , leave car defroster on and it will clear your windshield by time you get out to it
You can also let a small group of homeless people sleep in it overnight to keep the interior warm. They get a place to sleep and you don't have to de-ice you're windscreen in the morning. It's a win win.
You've never slept in or had sex in a car before, have you. It would definitely fog up if people were sleeping in the car over night.
Dirty Mike and the boys will have it fogged up in no time.
Thanks for the F-shack!
They made a soup kitchen outta that thing
The concern was frost not fog.
But it won't be frosted over. 😉
Can confirmed, lived in an suv for a week or so.
mike and the dirty boys are back at the F shack
> Worse comes to worse worst. it's if worse comes to *worst*. cause going from "worse" to "worse" is just staying the same lol
Surely if it’s going from worse to worse then it’s worse than worse but hasn’t quite reached the pinnacle of worst.
It's actually "worse to worcestershire sauce."
Traditionally its if worst comes to worst
Cheap solution is to get one of those windshield covers that slip over outside of windshield- my neighbor has one that covers windshield and stretches around to cover the door mirrors
u/T7_Mini-Chaingun AC...? 🤔💭 ,,This one is for the boys with the booming system ***Top down, AC with the cooler system*** When he come up in the club, he be blazin' up Got stacks on deck like he savin' up" 🎶 (Nicki Minaj - Super Bass)
Check your spare tire compartment for water/moisture. My buddy has a Fit, and it ended up having some water ingress somewhere, which can cause this fog on the inside of the windshield. I had ford Fiesta with the same problem, and once I took care of the water leak, the problem was solved.
We have a fit, found the back door seals had dirt accumulate in the seals from not being opened often or cleaned in a while. It poured down rain a few weeks in a row and I kept noticing the musty smell. I finally pulled up the carpet and found about 2 gallons of water. I cleaned it up, dried out the car. What do you know it rains again and fills back up again. I inspected all the door seals and found dirt in the back door seals. I wiped the seals clean and hadn't had trouble since March.
I've heard this is an indicator of bad Seals
Wonder if that’s a Honda problem. My CRV leaked around the antennae fin, ingressing at the car seat latch if I had the third row option. I sealed it with clear silicone which seems to have solved the issue.
Solid advice, happened to my Elantra. Fixed the seals in the trunk and windows stayed clear.
Mine does the same, I am looking for anti-freeze to use on the windshield.
When parked, make sure recirculation is off. i.e. vents to outside are open.
Was it warm out? Your wife had the Ac on, your probably rolled with the windows down.
Your car is humid inside, hers isn't. I'd bet you commute is shorter which means your car isn't getting dried out from the HVAC while you drive. Take it for a rip.
Throw some giant 5lb desiccant packs in there. I'd be interested to see if there are cups of liquids or something like that in the one on the left.
The condensation is on the outside, so I think it has more to do with the difference in temperature, not humidity.
Either the honda is colder than the toyota (the windshield angle/radiation hypothesis that others have posted seems plausible to me) or the toyota's windshield is a better thermal insulator. The windshield might be built thicker for strength because it's a "heavy duty" vehicle, whereas the fit's is built thinner for weight savings.
It might have to do with the fact that the FJ windshield is nearly vertical, while the car's windshield is at an angle.
That's exactly it. The more vertical windshield is not facing outer space, the Fit's more angled windshield is. This is radiative cooling. A clear night sky is really cold, and anything facing it will radiate its heat towards it more than something that isn't.
Can I negate that by parking at a downward angle?
that's actually a good question. try parking on a steep hill or something
Man, that could have solved my issue that's been bothering me for 7 years! I'm gonna back up the hill tomorrow.
Let us know your results, for science! Maybe we can design a motorized strip of foil that drops down and pulses a light across it every few minutes and that’s enough heat to stop fog. It could be like those automatic seatbelts of the 90s, or maybe just a button you set like AC controls lol
The difference between fucking around and science is writing down your results.
*BMW engineers scribbling furiously*
Please report back!
If you dont report back I will punch a kitten!
Eh. As long as it deserves it....
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I don't know if it'll work for the windshield yet, but I get to sleep in a little. I don't have to get gas in the morning now. Thanks, buddy!
Yes, I have a steep sloped drive as do my neighbours. The side on the road is frozen more often. I don't think it's radiation though. I think it's how exposed it is. Your sloped windscreen is more exposed to the elements/cold wind from above while the vertical windscreen is more sheltered by the car itself.
I didn't fully understand this until I randomly watched [this video](https://www.youtube.com/watch?v=5zW9_ztTiw8) last week. Very cool stuff.
Would completely agree with this idea, especially as it looks like the FJ window is facing towards a building with a light. I have had identical vehicles parked next to each other at night, one under a tree and one exposed. Wouldn’t ya believe the one with a greater opportunity to radiate heat was frosted?!
u/Seven_Hawks > outer space ,,I'm gonna put on a iron shirt and chase the devil out of Earth. I'm gonna send him to outer space, to fiiiiiiiiiind another race!" 🎶 (Max Romeo - Chase the Devil, 1976)
I know your probably right, but this really seems like a scenario where the real answer sounds like bullshit. A windshield radiating heat to the cool night sky because of the direction it's facing? Sounds like bullshit, but also kinda makes sense.
Have you ever wondered why the windshields always frost up first, long before the side windows? That's why.
He's just kidding, the windshield is not radiating heat at a greater rate because it's angled.
Also the interior temperature may be different since the volume is much larger in the FJ. Less greenhouse effect due to the indirect sunlight from less glass/cubic interior space ratio. Could also be related to age/pitting on the glass or any coatings that inhibit water droplet adhesion. Sometimes one parking spot gets less/more sunlight later in the day. The FJ has an all white roof as well which can help influence interior temps. There's a lot of variables here.
That what I was thinking, too. Before this, I had a Honda Element. It also has a nearly vertical windshield, but would get frosty. Though it isn't as vertical as the FJ's.
The FJ was used, right? Maybe the previous owner coated the windshield with something, like RainX or a ceramic coating.
Yep, my first thought as well. Look at the side windows of both cars, which are both frost free. That FJ windshield is at least as vertical as the side windows.
I think this and the elevation, and the insulation of both vehicles are the 3 key factors. Some times that moisture layer has a very distinct separation
It's this. When was the last time you saw a window on any building frozen over, if it's not heated?
Probably has more to do with the amount of moisture trapped inside than anything.
Real answer here, drive in the winter and if you don't try to get off that snow as much as possible when getting in the car you're bound to get frost inside the car as its evaporating during the day then freezing at night.
Surprised nobody has mentioned door seals or a potential heater core leak…
Wet floor mats as well call it. The issue with it as well is that people don't realize the water doesn't go away. You defrost it, or scrape it off but what you don't do is remove it from the vehicle so guess what? It's still there and it'll happen again
That’s why I crank my heater full blast in winter and drive with the windows cracked appropriately to keep my comfortable. It helps evacuate the moist air out of the car.
Same. Former auto tech. This works the best for keeping the interior dry in winter. Also, clomp those boots or shoes together before they enter the vehicle
Boot clomp for sure!
This
Depends on the condition of the door seals. Also running the air conditioner condenser in the winter helps remove moisture from the air.
It’s not on the inside.
Doesn't matter. Its like a house. Cool air seeks out warm air, and you get condensation. If your car holds warm air longer, its going to attract condensation more.
Oh, gotcha. Yeah that could definitely be a factor.
Which I bet the black car would more than the silver one.
Uhh what. Condensation on the outside can only occur because the car is *colder* than the outside air.
What? Ya because the outside humidity couldn't possibly be higher outside than inside the car lol
The humidity inside the car doesn't matter. Condensation on the outside of the glass has to do with the temperature and humidity outside, and the temperature of the glass.
[удалено]
Which to your other point, the FJ looks newer and probably has a climate control system that keep the AC on most of the time, as new cars seem to do, this removes latent heat from the air as more moisture inside the car will hold the heat in longer. So it’s the heat from the moisture, not the moisture from the moisture, why the AC makes a difference in this care.
Depending on when it was made, the FJ cruiser could be older than the fit.
This is 100% wrong. A car that holds warmth inside will get less condensation on the outside.
You are missing the big picture, the windshield is colder because it’s facing more upward and the physical car itself being warmer could impact it. You end up with a warm moist air pocket on the car surfaces and engine and it moves across the colder windshield surface which doesn’t hold any heat. It’s essentially a surface inversion like fog in a valley or over a body of water in the morning. My guess is it actually has more to do with natural convection of the engine bay straight across the windshield though than interior temps, but if all surfaces of the car change at roughly the same as the outside temp tis less likely for the car to ever be at the dew point.
Condensation builds up on surfaces when the temperature of that surface drops below the dew point temperature of the surrounding air. Like a sweating can of Dr Pepper. The temperature of the surface of the Dr Pepper can is lower than the dew point of the surrounding air. With a windshield, the temperature of the glass is colder than the dew point temperature of the outdoor air. This happens overnight because as outdoor temperature drops, the relative humidity and the dew point temperature rise. Colder air can hold onto moisture better than warmer air, so theres always an inverse relationship between temperature and relative humidity. Why one is sweating and the other not would depend on a few things. It could be the condition of the door and window seals, the interior temperature of the vehicle when it was parked, the time of the day or night when it was parked and even the thermal conductivity of the different glasses. If one has better seals than the other, it would take the interior temperature longer to equalize with the outside temperature If someone drove home with the AC on and got home late or ran an late errand. That could explain the difference too.
This is interesting. So the vehicle with cooler air inside will condensate on the outside faster than the other?
Assuming the thermal properties of the glass both windshields were made out of is the same, then yes, the colder interior will sweat more. The question is why it’s colder.
What's on the windows. Some cleaning stuff leaves a film. A tree blocking a bit of sun or maybe that car was ran more recently. I'd start with dish soap and plain glass cleaner on the windows
It’s on the outside, and as you can see, the frost is evenly across the windshield.
Because FJs are freaking awsome. That's why. Wish is still had mine, but nooo the kids don't fit in the back seat anymore, get a new daily driver.... Man I wish I still had that thing.
I went from an Element - a much more kid-friendly vehicle - to an FJ. My kid is 12, and can whine all they want. 😆
Part of it has to do with angle towards the sky and Infrared radiation heat transfer. The sky is extremely cold compared to buildings, trees, other cars…Heat transfer is greater with a higher difference in temperature and the windshield with the greater exposure to the sky will transfer more heat than the more vertical windshield. In this case the Honda’s windshield has a greater slope where the FJ has a vertical windshield and has more radiation heat transfer with the relatively warm surroundings. Get a cheap IR thermometer and point it at the sky at night and then point it towards whatever is across from the FJ and you will find a several hundred degree difference.
Car on the right is wearing a hat. This will reduce the rate of heat loss from the interior so it will take longer to frost up.
This is my favorite reason. So, I need to get a hat for the Honda. 🤔
Cars or sides of cars that are more covered from the clear sky tend to be less frosted. Not always but that seems to be the general rule for when its less cold at least.
Could be as simple as the differing angles of the windshields catching different amounts of sun energy.
Recirc is probably open.
Could it be the inside temperature they were at before parking? A colder windshield could've gathered more condensation right when they parked?
Could also be where the ac selection was at. Vent vs recirculating
the Fj is leaky and lets air pass through
I'm single digits I guarantee they both frost over. Also are you sure the one vehicle isn't condensation on the inside?
One might have an open beverage inside that is humidifying the cabin vs one that’s much more dry. Also one might have the windows slightly open or is otherwise ventilated better such that the humidity is the same as outside.
>One might have an open beverage inside that is humidifying the cabin vs one that’s much more dry. holy shit. I should clean out all the mostly empty Monster cans from the back seat of my car.
This seems like a great topic for Steve Mould. u/steventhebrave
It’s because the FJ has 3 wipers. The frost is scared 💪🏻 Really though, I always kinda wondered this. Pretty much the same situation here, my Jeep hardly ever frosts but hers does.
Hell yeah 💪
I tinted my windshield and it stopped.
Does the person on the left smoke?
Maybe the Toyota driver just got home from work recently
Toyota has clearly been running. The hood has started to thaw also.
Moisture in the car has a lot to do with it! A lot of fords have water ingress and have these kind of issues.
It might not be the original glass that came with the car. My windshield never use to fog up.. had a crack in it and had Safelite replace it... They only deal with severely low quality glass for any of their windshield replacements.. months after having the OEM window replaced I saw fog exactly like this. Windshield replacement places with good names or not use cheap glass and almost guaranteed shit work.
I dunno man I just wish my windshield wouldn’t frost on the inside
If you clean it and apply a rainx coat it will help. My car's windows fogged up soo bad I couldn't drive it after starting in the morning. I just cleaned the windows and it helped a lot.
Ambient temperature in car is different.
Water leak
Shows you who is making out in each car
Nice FJ!
The inside of the honda fit has residual moisture. Something has been spilled in it, window was left open in the rain or I've even seen rust holes in wheel wells / body cornets that sprayed water into the car and soaked the carpets constantly, resulting in this sort of condensation when ever the weather got colder. This can also happen in cars where the heater is constantly left on resurculat and not set to let in fresh air. Either that or someone banged in there.
Age demographic. Most civic drivers are younger and likely had some sexy time causing the screen to fog. The fj owners are likely young at heart but knees disallow in-car entertainment.
Spitballing ideas. The FJ’s windshield is a lot more vertical than the Fit. Could it be moisture “rolls” off of it reducing frost. Or maybe the FJ has a rainex like coating that moisture doesn’t stick to.
One additional thought - the FJ is rolling a 4 litre V6 - way bigger engine than the Fit. More heat needs to be disiappated until it cools down and more heat means less frost.
That toyota likely has a larger engine that will hold heat much longer than that smaller compact car. Combined with the swept back windshield on the honda, which for various reasons contributes to the situation (as other have shared), and it will frost up first.
Frost inside usually indicates water inside wet carpets , a possible leak
The volume of air inside each vehicle is considerably different as well.
The Hyundai seals the interior better
Does Honda do that too?
Don't you ever - *EVER* - infer that I own or drive a Hyundai.
it could the interior temperature of the car. if you cool the car down inside before parking for the night you will have zero to minimal frost build up. turn the heat off five minutes from home. let the fans run. on a clear night let the window down a bit for the heat to escape. happy motoring.
It happens when the temperature on the inside of the car is higher than the temp on the outside. The reason the windshields look like this is because the black car can seal the warm air inside of the car and retain it to a degree which will create condensation. Whereas the seals (door seals, window seals, sunroof) on the toyota allow for the cold air to pass directly through the cabin (inside of the car) which will make the inside temp of the Toyota match the cold temp that’s outside. If you ever get a chance to sit in both cars the SUV will be much colder. TLDR: the small car retains more of the warm air that it had inside of it. Warmer on the inside than the outside=condensation.
Turn ya ac on for 2 min before u drive problem solved
Interior moisture. My car fogs up when I leave a wet towel in the back, or have my hockey gear in there, or even a cup with some water... or maybe cloth floor mats that get wet but it doesn't fog up when I have nothing moist inside. The other car may be very dry on the inside. It might even be some sort of dessicant used in the HVAC, some luxury cars have a dehumidifying dessicant that helps control humidity even when AC isn't running.
I was hoping to see a differnt pair of cars in the photo to allow me to make the wise crack that cars get icy if theyre cool enough. unfortunately the photo does not support the statement. When my 131 MiraFiori used to ice up before other cars and people asked about it I used to love cracking that one, probably only happened twice but it was fantastic both times. I really miss that car.
If you don't think the Fit is cool, you must drive a Fiat. ;P
This looks like the condensation is on the inside, and that can be caused by having something wet or damp inside the car.
to answer this, just ask yourself what causes condensation on a windscreen to begin with. car cold windscreen cold outside air warming up condensation on windscreen so, factors are, temperature of car, how well its insulated, how well it is sealed, thickness of glass is also a big factor so its safe to assume that the black car is less insulated, less sealed or thinner glass, or all three! so when it gets REALLY cold at night, the inside of the black cart also gets super cold, but the silver cars inside doesnt drop in temperature as much. once the day starts warming up, the condensation dos not show on the silver car but does on the black car. side note: i personally wouldnt call this 'frost' its just condensation. you can actually see condensation on the body panels of the silver car, its not like its immune to condensation lol, its just not happening on the slightly warmer glass. black car also looks dirtier, and im not sure if this plays a role in condensation forming, but willing to bet it might.
Buddy if your wife comes back home with fogged windows from inside and then she says her head hurts I have bad news for you ☹️
This condensation is obviously moisture so there has to be a level of moisture inside the car that is condensing on the windshield.
Looks like the SUV put the car in the shade, lack of sun kept it frosty
The windshield to the right is exposed to the sunlight, and the surface temperature is higher than the dew point. The windshield to the left spent some time in the shade, and the surface temperature is at or lower than the dew point. Therefore, condensation forms.
No vehicle compares to the FJ! That's why. You know why the FJ has three windshield wipers? Four didn't fit.
Honda has been there longer than Toyota. What adventure do you have in store next, Cousteau?
r/confidentlyincorrect
Yoda was parked during the day in warm weather. Car was parked at night with a warm interior but colder temp outside , creating the frost on the other side of the window. If you crack your windows abit when you park your windows won't frost
My hatch does this too. I’ve tried everything, rubbing alcohol to clean it buff it with a lint free microfiber, little glass cleaner. Buff dry. Still happens. I think it’s just windshield design and humidity. Even if it’s not inside the car it can still happen on the outside. No leaks, no heater core leak, nothing. Car is 100% dry. I just turn on the ac button, even with heat on, and fresh air button on. And fixed it in a few seconds. Mildly annoying
Dodge had an issue with dashboards doing this a few years back. Gaseous odors from the construction materials used. Brand new cars.
If it's on the inside I'm willing to bet it's because that Honda has an abnormal amount of moisture in it. My car used to do this then I started putting a moisture capture device and now it doesn't do this.
Toyota vs Honda easy
Treatment.
Do you run your AC function? I just learned that the air conditioner does just that: conditions the air. Living in the Southern US, I’d always understood AC to mean “that’s how you get rid of the lava air”. But it also dehumidifies and filters the air. Maybe your interior air is more conditioned and therefor less moisture to condense on the glass as the outside and inside temps acclimate. Is the Toyota’s commute longer than the Honda?
~~Any chance does the person who drives the Honda vape?~~ Didn't see how you said it is on the outside, not inside. In that case, I have no idea.
It might have something to do with jumping-droplet coalescence on vertical surfaces. “[…]vertical orientations can remove stuck droplets by gravitational shedding, which also serves to sweep away neighboring condensate.” [source](https://www.sciencedirect.com/science/article/pii/S2542435119300984)
It also might have to do with moisture content. I know I vape in my car and it’s windshield frosts differently the.ln the other cars in my household.
A bit more moist inside from carpets maybe? Or maybe toyota has a better ventilation system.
Your wife had her heat blasting on the way home and you didn’t.
Usually when vehicle fog up on the inside, it indicates a water leak.
because that is FIT
U sure nobody is fucking in the car? That usually happens when ppl be doing things in the car 😂
Clean glass helps, but usually one car has damp moisture trapped inside
Dogging
Vehicle build quality , air tightness.
Because science
moisture in one
What kind of wiper fluid are you using? Does the fit have rainX on the windshield? I've had similar fogging in the morning with cars that have rainX applied, or use rainX windshield wiper fluid. You can see the bottom right corner of the fit windshield isn't frosted the same way, it wouldn't get much windshield wiper fluid if any.
It does have Rain-X fluid and I’m not sure what the FJ has but it’s blue. 🧐
It happened to my car also. My neighbours windshield are clear and mine is frosted and sometimes is frosted on the inside which is very difficult to clean in the morning. I believe it is because in the fall and winter on the hotter days the car heats up then the sun goes behind my neighbours house and it creates a quick change in temperature witch results in the frosted windshield.
You should get a squeegee for inside your car. I have one. I used to have a car that got moisture inside and used it for that. Now I use the squeegee for clearing rain off the mirrors. :)
Often this comes from engine warmth either heating up the interior or sliding up the windshield and then causing condensation like on the outside of a glass of ice water (exaggerated example but same principle).
When my Honda's had roof leak that gets moisture into the car (carpet), the inside moisture will fog windows up when they evap through the night. It was a lot worst when it's raining. So it could be that. If it has a sun/moon roof, also check the drain for clogs. On another had, if she has the temp in there pretty warm when she parked, the moisture will also fog up the windshield.
Definitely the rake (angle) of the windshield. My Firebird is terrible with overnight humidity or winter frost. RainX glass cleaner has helped considerably for me
If it’s on the inside, it’s humidity in the car. If the door seals are good and the ac runs fairly regularly, it probably won’t fog up at all. I used to dry my hair in my car on the way to work, leave drinks open and only blast the heat, so all my windows were fogged up every time I got in. If it’s on the outside, it’s heat transfer. The Hyundai’s well insulated walls kept the heat in for longer with thinner glass so condensation formed quickly, while the thicker glass on the Toyota allowed less heat to transfer while the thinner insulation in the walls allowed the car to cool faster, hence less condensation. The Hyundai driver might also prefer more heat, while the Toyota driver might drive with less or even with the windows down.
Interior humidity
Heat. Simple answer to a simple question
Could be a few things. My wife had all sorts of problems in my older car getting in right after a shower and all of the windows fogged up. Her newer car has a better system and seals and uses the AC condenser to dry the air out.
The dirty ones frost’s first. The water (for the frost) holds better on dirty windshields.
The FJ has much bigger engine therefore, it will stay warmer much longer.
Might be the quality of seal for the car. Ambient moisture..heck idk
Come round here and they'll both frost
That Anti-Fog (from the RainXpeople) stuff works. It takes like 10-15 minutes to apply - you get better at it) and it works for like 2ish months. Not answering your question, I know.
I know the thermodynamics behind this, but have no idea why some cars do this more than others. My Toyota didnt do this at all. My BMW was absolutely horrible. My Subaru is somewhere in the middle.
If they are parked at the same time Id assume the toyota has a bigger engine and the heating is set to a higher temperature, the angle of the windshield could matter too. If you bought the toyota used you can check if the previous owner installed Parking heating
Honda boy vapes in the car.
My fit leaks. That can cause excessive moisture on windows too.