Heat, fogging windows, "burning" smelling steam

About 4 weeks ago, I left my windows down and it snowed. After that, the windshield fogged up really bad whenever the engine was to temperature. Then, a white steam(smoke?) started coming up from under the dash whenever it was at temperature. Now, the steam comes after making turns or going around curves.

About a week ago, the car started blowing cold air when the heat is on.

Today, I finally look at the coolant reservoir and it is empty with orange dirt/dust inside. (yes, i'm an idiot. now let's move on...)

I'd imagine these are all related, since I had no problems before leaving the windows down.

The car NEVER overheats.

Should I add water to the coolant reservoir and take it for a spin? It's scheduled to go into the dealer tomorrow and I expect them to tell me it needs a heater core. ($$ouch$$)

What steps should I take here? Thanks!!

First course of action would be to fill the cooling system.

You may be getting mist inside because there is moisture in the system. This could have come from the snow (I got my Jeep rained into once, took a couple weeks to dry out and had foggy windows during that time. Ran the AC constantly on recirc until it dried) or as you said from a bad heater core.


edit: Whups just noticed the date of your post. What was found? Let us know, it could help other folks.