The a/c evaporator is behind the glove box area it is built into this assembly that is a big plastic box that contains the air conditioning and heating system, basically when you turn the a/c on in your car the evaporator turns the heat in your car in to condensation and then water drips off the evaporator into the bottom of the plastic box where there is a drain hose which intern drips out a little tube that sends it outside of vehicle.So when this little tube is plugged up, when this happens the plastic box fills up to the brim with water and it starts overflowing onto the floor because it has no where else to go. If you go under car between the 2 front wheels towards the back of them and look up it is located on or slightly under the firewall just in front of the glove box area its a little 2 inch tube. stick a piece of wire into the little tube and wiggle it around and try to clear hole. Basically if your sitting in the passenger seat and your feet are resting on the floor the area above your toes would be the plastic box and the area below your toes would be where the drain tube is located on the outside of the car.
