We just went through a bit of a storm where we got over 9 inches of rain in two days. My wife was doing her usual 60 mile round trip commute.

Yesterday we went to get in the car and the passengers floor had a puddle of water.

My first thought was a drain plug clogged in the engine bay area but couldn't find one. On my Jaguar it is called the duckbill drain that allows the outside vents to drain water. I didn't see any on the Volvo.

Next I crawled under the car and saw that there was a rubber sealing plug missing on the chassis under the passenger floor boards. There are holes for three and one was missing.

Our car parks in the driveway on a slant. I pulled the rear plug and water poured out of the hole.

My guess is that sitting on the slant, the water just sat in there like a swimming pool and eventually found its way into the inside floor board. One sealing plug is solid and the other plug has a hole in the middle with slots emanating around the hole. I guess the slots allow it to be flexible.

The drivers side had no sealing plugs and no water inside on the floor board. I guess not having that rear solid plug allowed all water to egress.

I have friends that say using such plugs keeps moisture in and allows rust to start. Other people feel that plugs keep water out and you don't need to worry about rust.

Should I go buy the plugs or keep open holes that the air can flow through and dry out the stamped chassis.

The next idea would be clogged sunroof drains and / or clogged AC tubes.

Once the floor is dried out, plug the holes. Sounds like you got water in because a plug was missing and it moved to the rear of the carpet. Remember, the foam padding will absorb a LOT of water.

9 inches of rain? That creats a lot of puddling on the right side of the road which should then splash up more on the passenger side.


Water should never get into the car, it can do considerable damage if left there. I doubt that the sunroof drains are clogged, but it is easy enough to check: pour 1/2 cup of water into each drain hole, the water should immediately pour out beneath the car.

Thanks for the reply.

I'll run a bit of water down those sunroof drains and see what happens. I once had a car that the sunroof drains would constantly clog.


I pulled removed the kick panel at the side of the door and pulled the carpet back a bit. That is one think piece of foam and will take a while to dry. Multiple times I've using the wet vac today trying to wick the water up through that foam.

The best way would be to pull that carpet but before doing it I'll see if using the AC pointed to the floor to see if it can dry. My wife drives the car 60 miles a day and if she uses the AC to the floor the entire time it may do the job.

The sealing plugs are only $2.40 at the dealer. I could get them for a few cents less on line but then I would be paying shipping.

Yes nine inches was crazy and we had a lot of flooding. Aside from a wet carpet in the car, I need to remove a wet carpet from my house basement. The weather people were caught off guard on the severity of the storm.