When my engine warms up and I turn on the defrost it blows out a hot fog that has a slight antifreeze smell. If I run the defrost very hot and for a long time the steam decreases & eventually stops. However, after the engine cools the steam starts again as soon as the engine warms up. I suspect coolant is dripping/condensing inside the heater area when the engine cools but I can't see any leaks, visible water or even moisture in the engine compartment or under the dash. I'm not sure where to look or what I may need to open/disassemble to inspect and repair this problem. On cold & damp days I can't use the vehicle because I can't keep the inside of the windshield clear enough to safely drive. If anyone could provide some guidance here I'd be most appreciative.