Does this happen to anyone else? I can leave and while I'm driving with the defrost on every window will fog up. So I can't see anymore and i'm trying to scrap my window while I'm driving and can't see.

Is there something I can do to fix this? Thanks

 

Is the heater working?
Are the defogger ducts in place?
The fan speed control has a switch at the high speed end that pulls up a seperate relay for max speed.
That relay connector can go bad & limit your defroster output.

I don't have the S4 heat & AC manuals, but the S5 is similar.
Check section 16-heat & AC in the 89-91 FSM.

 

You are out of freon.....or however you spell it. Its the stuff that puts out your A/C. Get your freon filled in your car and then you will be good....in the mean time just crack one of your windows and your defogging problem is fixed. They used to sell freon in stores but stopped...due to there reasons, so know you have to pay someone to do it...

 

The heater works just fine, I don't have A/C anymore. Also it really doesn't fog up on the outside just the inside. I have to take a scraper and scrap the window(I get snow or something of some sort that will scrap off the window) If i turn the defrost on to cold and full blast it helps a little but makes it wores inside and i just freeze, and if i turn the temp to hot again it will just fog up all the way again...

hope you can understand that ..

 

Even without the condensing effect of the AC, the defogger should clear the windshield.

I just had a thought - heater core leak..

To fix - try Aluma-seal.

 

Dont run with recirculation as it reuses the humidifyed air inside the car and blows it up on your windows

 

I am willing to bet that is your problem. Even my REPU with huge amounts of airflow through the door seals will fog up if I have defrost on recirculate.

 

Yep, don't go on recirc- AND you may have a small leak in your heater core. Smell coolant at all? It only takes a tiny amount to make the windows fog up- and it will fog up with a little bit of slimy substance (coolant)
Worth the check. It's not uncommon.
BTW, don't bother with the AC.

 

Think of it this way, the window is fogging because it's warmer in the car than outside. Make the windows on the inside cold like the outside. You don't need heat to do that.

 

I bet this is the problem. Even though it is below zero out and I am freezing my butt off I have to allow fresh air in to keep the windows from fogging (on any jap cars, american cars do it without asking).

When you're in the car you are putting gobs of humidity in the air (your breath) and it condenses on the cold windows. The air out side has very low humidity and letting the fresh (yah I know cold) air in will keep the windows from fogging. Once the heater is warmed up it isn't bad. However don't use the "Bi level" setting (face and feet at the same time). If you use the fresh air setting with the bi level setting you will get cold outside air to your face and heated air to your feet. Yes that is how it is from the factory....Consult your owners manual. With the fresh air comming don't have the air shared between to places.

When's it going to warm up anyway......

 

Actually, the bi-level setting blows cold up top unless the temperature lever is set at the hottest setting. Then it is supposed to blow warm in your face. The bi-level setting is great for long trips in the winter when you don't want the heat to lull you to sleep.

 

That is not what my owners manual states and that is not how my car works. To get warm air out the vents or def it has to be on recirculate if shared with the feet.

 

That bit would be wrong. A/C is absolutely the best way to clear fogged up windows, so it's a shame he's removed it because this wouldn't be a problem otherwise. If you're blowing cold, humid air you're always going to be struggling. The A/C and heater should be used together. Warm, dry air will clear even a heavily fogged window in seconds.

 

I really don't think so.

Since Nebraska is bombarded with moisture lately, I think excess moisture is causing the "fog" on your windshield... Or your heater core is leaking.

Hope the latter is not it.

Do you see wetness under the carpeting?

 

Of course if your heater core is leaking, you will smell the antifreeze.

AC plus max heat will speed defrosting up the most but AC is not strictly necessary.

Recirculating the air will make defrosting more difficult but you can be forced into recirculating if you have heavy snow in the external air intake at the base of the window. If so, you'll have to crack open a window.


That's all I know about defrosting.

ed

 

I think the heater core is leaking. I might smell a little antifreeze now and then. I will have to check under the carpet to see if its wet. Should I look on one side or both?

Also to change the heater core you have to take the entire dash off right?

 

ok, screw all that heater a/c ****, and try this:

take a small amount of dishsoap, any kind, and rub it all on the inside of your window. Take a paper towel and rub it in all over. you should get a white glaze. take another towel or cloth and keep rubbing till it turns clear again. My friend did it on his FC and he never has problems. seriously try it.

 

Yes you have to pull the dash. No other way. It isn't as hard as it sounds.