4RUNR

Everything freezes on the inside of the windows and makes it impossible to see anything except something with high beams on 30 feet away. Very dangerous! Full heater output directed to the windshield gets about 75% of it clean. Side windows stay opaque from the ice.

p.s. Does recirculate in heat mode mean it gets warm air from inside and heats it up more?

jdecker

Use fresh in heat mode to prevent fogging and ice. Recirculate only makes it worse.

jimbo74

recirculate with the air conditioner on works wonders for the interior.. it gets even coleder inside though

digital0ne

Circulating in fresh air will prevent the humidity temperature and stagnation from causing condensation to form on the inside of your car.

Personally, I leave the vents open and on defrostall of the time that I am not using the system to cool or heat for another purpose.

Cracking a window, even slightly will also, as jimabena said, "works wonders". I usually drop the back window down a couple of inches, or even crack the back seat passengers windows an inch or two.

Finally, if the problem is chronic, I do believe that there are products sold to prevent the adhesion of moisture in the form of condensation on the surfaces of choice (for this example, I'll use 'glass'). Rub on the polymer, and it has basically a "teflon" affect, providing a surface that water will not stick to, or run strait off.

Any one know the actual name of this "magic-fog-b-gone" product?

leebee

im not sure about your runner, on most newer vehicles when you select defrost your a/c comes on automatically to remove the moisture from the air. mine is a 93 but my a/c went for a crap this past summer, i dont think mine has that feature anyway.

lee

CynicX

Defrost against the windows should do it, I think outside air will work the best. I may be mistaken but if I turn on defrost it automaticly turns off recirculate, so I'm guessing Toyota decided that works the best....it could be the opposite though I need to check.

The makers of Rain-X also make a product called Fog-X (i think thats what its called)...you put in on the inside of the windows to prevent fogging....I dunno how well it works though....

Bluedog

ditto on leaving the defrost on all the time. I have mine set on the defrost/feet setting.

PirateFins

Defrost with the fresh air selected, recirculate keeps the moisture inside. You can also put "Fog-X" on the inside of the windows. It is made by the "Rain-X" Co. the only problem is you get a nice contact buzz from it until it completly dries.

4RUNR

That's the trick, I never noticed any difference whatsoever when using recirculate in the heat mode.

The problem is not really fog, it's *ice* on the *inside* of the windows that forms while the truck is sitting outside. Turning on heat does not make it go away. There is simply not enough output to overcome the heat that the glass loses with the outside.

Only two options I think are prevention, and scraping it off, which will be difficult as the ice is extremely thin and hard.

I'll go find a bottle of Fog-X and see what it does. By the way, would it be a bad idea to stick something in front of the grille to block air flow? When it's slightly below freezing outside, the heater output can bake the passengers, literally painful to hold a hand against the vents. When it's cold out, the air is warm, at best.

89macrunner

lol you want fresh air ALWAYS when you have the heat on. your bodys heat and moisture evaporates and comes back out again (well thats what ithink happens atleast) and it keeps getting more and more moist..heres how it goes

Heat - Fresh Air

A\C - Recirculate (cools the cool air)

TACOMANATOR

Fresh air, AC on and the heat up. AC dehumidifies the air, heat thaws the frost/ice, and fresh air helps keep the humidity out from your breathing.
If that does not work, stop breathing.

TechWrench

The frost on the inside of the glass means there was too much humidity inside the vehicle when it was parked. With my vehicle, it depends on the degree of outside humidity as to how I set the controls. If the outside humidity is high, I start with defrost, air on, temp up, and recirc on. This will let the air remove as much of the humidity from the inside as possible, then I switch to fresh air. If the outside humidity is lower, I go straight to fresh, unless I have a car full of passengers, then the interior humidity level might need recirc to clear it up.

alanh

4RUNR

About blocking the grille.

I'm not sure if you're talking about the radiator or the heater intake. If the latter, obviously not going to do what you want if you select outside air and its blocked. If its the radiator, you'll see lots of semi trucks with things on them to restrict the air to the radiator when it gets cold. I don't have any reason to do that in Seattle, but my dad used to put a piece of cardboard in front of the radiator on his pickup when I was a kid in Idaho. He drove a couple of miles to work so it helped it warm up faster. I did it once on a trip with an old truck on a winter trip because my heater couldn't keep the cab warm going down the interstate; I think the temp was somewhere around -5 or -10 F.

The key would be to make sure you're not overheating by watching the gauge and don't forget you've got your cardboard or whatever there when the weather warms up. Cardboard may not be a good choice if you drive in rain either.

leebee

those big rig shutters are also motorized, they open and close to help regulate the engine temps. if your rig isnt getting enough heat, you want to check out your system and repair any problems. you sure dont want it crapping out on you in the winter and leaving you stranded in the cold. until you get it repaired, carry cold weather survival gear with you, it will take up some room but it will save your life.

lee

Sherpa

I think you have too much moisture inside the vehicle. It is there either because of a leak, or more likely, tracking snow inside. When recirculate is turned on, the system cannot evacuate the extra moisture from the vehicle. The fastest way to get rid of it is to dry out the vehicle by allowing fresh air in, and running the defog setting.

Keep in mind that the colder the ambient air temperature, the less mositure it can hold. When the outside temperature is below freezing, it shouldn't take long to dry out the inside of the vehicle.

-S

4runnerx4

4RUNR, I have used the fog-x and in my opinion the regular rain-x works better on the windshield than the fog-x for preventing fog/moisture on the insde. I was on a job up in northen michigan and i had at the time a small leak in my head gasket on my 85 4x4 and the windshield would stay fogged from moisture coming in the vents. Sometimes the inside of the windows would freeze and a thin sheet of ice would form. So untill i was able to fix the head i tried fog-x and rain-x and the rain-x worked better. Hopefully you do not have the problem i had because it was a real pain, the truck ran perfect and you could not tell by the way it ran that the head had a bad spot in the gasket because it was so small. Trying to drive it though the windows would fog up slightly and reduce the visibility. You could wipe them of with a towel and within miniutes they would refog. Not a (i cant see through fog) but a light clear/cloudy fog and at night when i shut down the next morning it would freeze.

Bigblock

i had to remove my carpet cause it wouldn't dry out.it's easier to hose mud out now.water runs out plugs in floor.

cstem

For the heater not working well- check Tstat- if the opening temp is too low, the thing opens and cools too well.
For the interior moisture- crack a window when parking the vehicle overnight. The moisture from you and your passengers will vent out better. (think a tent when camping- airflow is needed to keep moisture out)
A/C does dehumidify as said. In fact GM oweners manuals from the early 90's tell you to use A/C to defrost.
You really want to avoid moisture inside- fog-x does not eliminate, just lets it run down to glass onto your interior. Craking the windows some (if parked outside get some rain deflectors) should really help.

Phssthpok

Your first task is to find, and eliminate (if possible) the SOURCE of the moisture. (there have been many sources listed already, I'll not rehash them)

Second, get the cars interior warmed up enough to get ALL the condensation off the surfaces ( if possible), then go for a drive and vent the cabin air out through wide open windows. (obviously not during rain or snow as this would allow precipitation to enter your cabin, defeating the purpose). Repeat this warm/vent cycle as many times as you feel it is needed to dry out any upholstry you think may be retaining moisture.

Finally, if all else fails, purchase a small space heater with a blower fan for circulation and purchase a Dri-Z-Air unit. They are cheep and work like a charm, though they are not FAST... it will take about a week to fill it's resevoir, but if you leave it in your car, it will do it's thing every time the air gets warm enough to hold moisture (read: above freezing). Use the space heater to keep the air inside your truck above freezing overnight so the DZA unit can do it's thing. In about a week or two you shouldn't need the space heater, as your normal driving should warm the air long enough for the DZA unit to keep any recurring moisture under controll.

Beware though..the crystals inside the unit are NOT child/pet safe.

4RUNR

Well, the source is obvious. Opening the door to get the snow brush, then opening another door to get in coats the inside with snow. Even though I have rain-guards, opening windows even a smidgeon when it’s windy and snowing would result in a snow drift on the seats.

I tried Rain-X on the inside, since I had a bottle anyway, and it *seems* like it's not forming ice in the same place. But will have to give it more time to be sure.