Water on floor boards?

Unfortunately these are not the easiest to find on newer vehicles like this. If this issue just started then the common things are sunroof drain tubes being clogged but normally this will stain the headliner. If you don't have that then you are correct it is coming in from the cowl area most likely.

The way to find this is to first remove the carpet from the side that is wet. You will want to do this anyway because you want to dry out the carpet and the pad underneath. If you leave it in the vehicle to dry it will start to smell.

Once the carpet is out, you want to start water testing this. The way to test it is testing from low to high on the vehicle with a garden hose. You don't want to spray the water, just let it cascade over the area that you are targeting. Clearly you will want to continue checking inside the vehicle for water running inside which will be easy to see with the carpet out.

Let me know if you have questions and we can go from there. Thanks

If you can narrow down the area, then use this product that I attached. Clearly you don't want to just go wild with this because it is not that cheap. However, if you can water test the area and then start using more directed or target methods to find the area that the leak is entering the vehicle, this will work. If the area that the leak is coming in is not reachable with your hand, just attach a clear plastic hose to the end of the tube supplied with the kit and apply this sealer as close as possible to the entry spot.

It will flow into the crack/opening and seal it. This will prevent you from having to take the body completely apart to try and reach it.

Let me know if this makes sense or not and I can try to find a video if needed.

I think you meant to say water drain. Does this have a moon or sunroof?
You may have to just sit in the vehicle with the garden hose in your hand from the drivers side, hold the hose on the roof and run water all over, waiting for the water to enter the vehicle so you can pinpoint it. If need be remove any door panels, pull up any carpet, remove the interior trim around the back window so you can get a closer look. This video will help you fix it

https://youtu.be/q9_MZiS2_NE

Please run down this guide and report back.

Another good way of checking for body water leaks is the drive through car wash, have someone in the back seat checking door seals for water entry.

Is it just after raining?

Roy

Are you using the air conditioning?

Roy

Checked for being clogged allowing water into the inside compartment this video will show you how

https://youtu.be/q9_MZiS2_NE

roy

Yes, under the dash. The ac system will sweat water and needs to go outside the car for draining.

Roy

The rear floor is lower than the front and it will flow to the lowest point

Roy

Yes, 1/2 hour labor but the clean up takes a lot longer for you to do.

Roy

I worked on a problem like this one before.
Open the hood, on the passenger side where a bunch of wire inter behind the dash at your right side at the passenger side. Those bunch of wire goes to the computer.
Now, where the wires enter the coal from the engine compartiment to under the dash, it should be sealed there, if not, water will enter there and run down the interior carpet on the passenger side.