busted raditator , check heater-core . most are found inside up under your dashboard . hope that helps you !
sounds like there could be a plug knocked out of the firewall on the passengers side which would allow water to enter when you hit some puddles and splashed up
overfilling
Could be that your heater core is leaking May also have a plugged evaporator hole.
It could be the heater core leaking.
You have a hot water line leak under your floor -- you have to remove the floor and repair pipe or run it over head. Call your insurence company to see if they will help with cost
Heater core is leaking. Air Conditioner drain hose is plugged.
Most likely cause would be the floor has a moisture problem or the floor was not level when it was installed. There is always a chance if it is fairly new that it is defective.
The side kick panel is to the right of the floor where the passengers feet would be.
Check the AC evaporator drain line...is it not connected to the outside
the water
Leak on drain line above floor level
insanity