I am still trying to find where it is leaking inside my 1999 Lincoln Towncar. I have had the AC drain tube professionally blown out. I have checked the window and door gaskets and they are fine. It is not leaking in the trunk area, just on the passenger and driver sides of the car interior. I have checked to see if the antifreeze is leaking and it is not. I have been parking it under a carport and it is still getting moisture inside the car floorboards somehow. I have made sure that I do not run the car through any automatic car washes that wash the bottom of the car.
I would like to know where else to check for leaking in my car. I just get it dried out and then it is wet again. I have tried driving it without running the air conditioning at all and that doesn't help. Does anyone have an idea for me to try?? This car has the fake look cloth/hard convertible top, I have used the garden hose and hosed the car down for quite a while and then when I checked it for leaking I still couldn't find where it was leaking. Please someone help me!!

First have a friend sit in the car. Spray water on the front windscreen, it could be coming in the windscreen seal. Or the water can run off the screen into the engine bay and leak from there. Find out how far the damp/water comes up inside the car, look for a leak at this level.

Some cars have drain holes which plug up over time from dirt and sediment deposits. If your car has these, trying blowing some air through them.

I also saw a car once that was leaking onto the floorboards because it had rusted through behind the wheel. We had to take a hose and keep it sprayed on there and eventually the water started coming into the car.