I have a 2000 Civic and recently it has started getting wet on the driver’s side floor (and back seat floor on the driver’s side) when it rains outside. I have had the front windshield replaced several times because that would seem like the likely problem. However, that has not changed the situation.
Please help if you know any other reason why this could be happening! I have several mechanics stumped.
If you have a sun roof, that is the most likely problem. Look for a blocked drain, there would be four of them. Sun roofs don’t rely on sealing to keep you dry.
If you don’t have a sun roof, I would look for a blocked drain in the A/C evaporator unit or a blocked drain in the air intake (the area under the grill right in front of the windscreen.