Passenger rear floorboard flooded after rain

TOOSH7849

MEMBER
2005 LINCOLN TOWN CAR
6 CYL
2WD
AUTOMATIC
100,000 MILES

Rear passenger side floorboard fills with a puddle of water every time it rains. The front passenger doesn’t get wet. I’ve cleaned the plug under dash from debris and this still didn’t help. No sunroof, no water in trunk, no water in door panel and this happens when the car is parked at home, and it rains rather it be parked at a slant or parked on flat ground. What else should I check? I’m not sure the next place to look for a spot for water to get in and hold to the point it’s a big puddle.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

More than likely this is coming from the door if the rear floor area is the only thing getting wet.

However, we need to start testing this by running water down the back glass so that it only runs to the trunk lid and not the rear door.

This way we can make sure it is not entering through a body seam in the rear trunk. I understand that the trunk is not wet, but the water can run down what is called the dog leg, which is the front part of the wheel well.

If you run water for an hour like this and have no puddle in the rear floor move the hose to the rear door. However, try to run the water over the door in thirds. Meaning run it over 1/3 of the door then 2/3s and then the full door so that you can slowly find where the water is coming in.

You will want to remove the inner door panel and the carpet as much as possible so that you can see where the water is running.

https://www.2carpros.com/articles/door-panel-removal

I am attaching the info below on how to remove the rear panel. Let me know what you find. Thanks

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