Problem: You often see water on the carpet, especially after running the air conditioning.
Cause: The evaporator's drain has become clogged and condensation is leaking into the cabin instead of out of the bottom of the car.
Solution: Clean the drain. Some people have success simply using a pipe cleaner to clean out the little drain pipe, which is near the center of the car side to side and is approximately below the center console front to back. The best solution however is to clean out all the mess that's accumulating in the evaporator.
Credit for pics goes to Slo_Mo
There are other solutions as well, such as using the drain from a galant, etc. Probably the best thread for this is here:
http://www.club3g.com/forum/problem-reports/95892-c-leaking-water-my-floor-board.html
If your AC is draining properly, the issue is the seal around the door. This most commonly fails right by your tweeter. Replacing the gasket is the only solution of which I'm aware.
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Water, wet, carpet, leak, floor, floorboards, A/C, AC, air conditioning