Originally Posted by SonofaBonny
I don't understand the "AC water evap" area thing at all
The evaporator and heater core are located in the air ducts under the dash. When the evaporator gets cold when you run the AC, moisture from warm, humid summer air condenses on the evaporator coils and drains through a tube to the outside of the car. If the drain tube becomes plugged, condensate can build up and find its way to the inside floor of the car. It should not, however, smell like coolant. The condensate starts out as pure water, and may pick up any dirt or dust it finds on the way to your carpet, but coolant should not be present.
If you have coolant leaking on the inside of the car, the only source is the heater core, unless coolant is spraying through an opening in the firewall somehow, like from a leaking heater hose at the heater core. Possible, but not likely.