On my '85 GSL-SE I'm having trouble with my windows fogging in cold weather. I don't smoke and the car has not been smoked in. Yet the windows are fogging like they're very dirty. When I clean them they seem to have a slimy residue on them... But I've cleaned them with vinegar, windex, and auto glass foam cleaner - they are clean but act like they're dirty - either that or I can't get them clean. Also the fog seems un-natural - with air flow and temps that would normally defrost them the fog seems to remain.

I don't think my heater core is broken because a) there's no visible fog coming from the vent, b) only a verrryy faint smell of coolant, and c) nothing wet and no evidence of leaking under the dash.

Yet on the other hand, my car seems to be loosing a little coolant over time. Though there's no abundance of white smoke when I'm driving and also there are no puddles after parking and no evidence of coolant leaks in the engine bay. I'm wondering if maybe while driving the coolant could be seeping onto the engine, quickly evaporating, and then being sucked into the cabin by the fan?

The rear tire well has no water in it, though I shoud really double-check that. Also I suppose it's possible that my recirc flap is sticking half-way? I know that if I intentionally turn recirc on it fogs much worse so it's not stuck fully on recirc.

Would really appreciate any thoughts you guys might have.

 

It sounds like the GM plastic plauge. GM cars have some sort of plastic that gives off a gaseous residue that forms a film on the windows. That film gives moisture just enough to stick to to freeze and fog.

Get some coffee filters and try wiping the glass down with those.

Otherwise I'd look into some weather stripping, keep the moisture out of the car to begin with.

 

Definately a heater core leak. Slimey residue gives it away. You don't necessarily get fog from the vents if the leak is small.. You shouldn't smell any coolant when sitting in the car.. Even a faint smell is a giveaway.. Sorry to break it to ya.

 

I used Meg's #40 (I think) Vinyl and Rubber conditioner throughout the car in the fall - that could be it too. Initially this is what I thought, but since I've tried cleaning so many times with no help, I sort of ruled it out.

Partsguy - Shouldn't I be able to detect the leak up near the heater core then? Could there be a leak small enough that only vapour leaks out and no actual liquid? Also the coolant smell is not strong at all - much less strong than my '84 GSL which must have a core leak but yet the GSL doesn't show the fogging problem.

So no one likes the theory of vapour brought in by the fan then?

Ok, I'll do a much closer investigation of the core... I also should note that one time I left my car idling with heat on max for 30 minutes while shoveling the walk, and I left it on recirc to warm the interior. When I got back to the car the entire thing was COMPLETELY fogged. So that does lend credence to the core, unless the fan theory holds any water at all.

Good lord, how do you get the core out to change it? Does the whole dash have to come off?

 

I believe it does. The core is burried WAY up in there!

 

If the leak is small enough, yes, vapor only can be emitted.. Eventually the leak will grow and your passenger will have a very bad day.. LOL

You can have a dye pressure test done that will determine where any leaks are.

If you think about where your blower motor draws air from, you'll realize that it doesn't pull it from inside the engine compartment, thereby reducing the chance of bringing in burnt coolant (or any other nasty) smells.

I believe the dash needs to come out.. Not that bad of a job.. Just time consuming.. I could be wrong, though.. I've never done it in a rex..

 

If you take the dash off make sure you stay organize and maybe take pics. I took mine off, and it took me forever to figure out which screw went where. You have to take almost all of the trim off so it is a time consuming job. Good luck with your problem.

 

Well shyte.

Thanks for the input guys.