After a rain, water accumulates in the passenger rear seat floor. Short of putting a cover on my car before a rain storm, how can I fix this.
Do you have a sunroof? If so, I suspect one of the drains is clogged
If the sunroof drain is the problem there are lots of You Tube videos showing how to clear them.
The car does not have a sunroof.
There was a video about a small flap/drain on the same side under the hood. I cleaned it out as the video stated, but still have the problem.
You might have a window that isn’t going all the way up.
Check the door seals
It could be the passenger side door drain. Water runs down the window and then past the rubber seal. There is a drain at the bottom of the door to let it out. Check the carpet on the vertical part of the foot well under the door to see it it’s wet. Also check the carpet on the firewall to see if the water is coming in from the windshield or through the firewall. After it rains, of course, and before you drive it.
I’d think if water were coming in through the windshield it would be present on the front floor as well but the OP only mentioned water on the rear floor.