1998 lincoln town car

If you notice a 'sweet' smell, or windows tend to fog up, it's your cars heater core leaking. The heater core is located under the dash, passenger side, it's like a mini radiator. The cars cooling system directs hot coolant to it so you can have heat. To change it is an involved procedure.
If there is no evidence of the anti-freeze smell or windows fogging up, and u have been using your air conditioner, it would be a blockage in the drain tube from the a/c. The end of the tube is located under the car on the passenger side , behind the front wheel. The blockage needs to be removed, and will solve the problem. Let me know what u find Curt