From everything I read previously, wet/damp carpets in the front footwells, unless you've been driving in seriously heavy rain, puddles, etc. is THE primary symptom of a dripping heater core/hoses. If you are running your ac- it could be water sitting/dripping from your ac evap core. Otherwise a leak could be from the windshield, door window seals or the cowl/vent- but these would only leak if you are driving in wet conditions which would cause water to come into the cabin. Hope you find the source of the steenky!