What Causes a Lot of Water Under the Car Floor Mats?

[DeErin]

Reasons for a lot of water under the car floor mats: 1. Check if the sunroof drainage pipes are clogged. Fully open the sunroof to see a groove. Slowly pour water into the groove (the sunroof drainage pipe) to see if the water drains or gets blocked. The outlet of this drainage pipe should be located on the A-pillar or C-pillar of the car. 2. Inspect the door drainage pipes. Open the door, and you will find many small holes at the bottom—these are the drainage outlets. Check if they are clogged. 3. The door may need to be disassembled. Many small advertisements or business cards are often stuffed into the gaps between the door and window. If they fall inside unnoticed, disassembling the door may reveal wet clumps of cards, which not only block the drainage outlets but can also cause water leakage. 4. A malfunctioning air conditioner may leak water into the passenger side footwell.