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When I take the temp off anything other than the coldest setting a ton of gray smoke comes out of the vents. It doesn't smell, just grey smoke. Would this be the heater core?
If it was your heater core you would have a strong anti freeze smell. I know, because mine leaks intermittently and will have to be changed. The core is not an easy fix.
Check the evaporator drain. It's likely plugged and holding liquid around the bottom of the evaporator and making a swamp over night.
The drain is behind the passenger side front tire, on the bottom of the evaporator case. You'll probably need to get it on a lift. If you don't see a puddle of water behind the passenger front tire after stopping for a few minutes, the drain is plugged or it's a very very dry day.
Good luck,
formerly of Drumright.