My mechanic modified that flap because water would not drain fast enough and got backed up. Our Crossfire is kept indoors except when we are driving or if it is at the mechanic so I can’t say whether this solved the water issue. When the mechanic last had our car to replace the fuel pump it sat outside for several days and got water on the passenger side floor and inside the passenger door. Drain tubes under the windshield Cowell were clear of debris.