I have a 1996 Park Avenue that just started leaking on the interier. The water accumulates on the floor of the drivers side and the rear floor on the same side. I don't see any obvious water entry marks. Ther is a substantial amount of water. The only place I can think of that the water enters from is the side interier trim platic molding around the door. The windshied seems to be OK. I don't find any drips anywere and there aren't any wet spots that I have been able to find on the carpet. I have to take a shop vac to remove the water and try to dry the carpet. This just strted this winter. I have had no other problems with water in the past. Any suggestions?

Take newspaper and slip it over the window and in between the
doors and the body close everything tight ,take into a automated
car wash sit in it and watch you will see the leak. Have you used a
roof rack on the car this can cause a leak. It more than likely a door
or window rubber seal that is cracked. Armorol can help to make a better
seal.