So I bought my wife a 2007 Expedition a couple weeks ago, and she absolutely loves it for driving our son around...except that we've noticed that the passenger floorboard gets wet when it rains. We have not noticed it doing it with the AC on as an old thread here suggests, so I'm not sure that it is water condensing from that, I'm pretty sure it is coming in from the outside (though I will be investigating that little drain tube to make sure). Any suggestions on where this water may be coming in from? I've had the carpet up and the glovebox out, but I haven't really had time to dig much further than that. I've thought about the windshield seal but I would think I'd see something from the outside.

Does the HVAC intake under the cowl have any kind of trap or door that is supposed to keep water out?

Any help steering toward the right direction would be awesome.

Thanks in advance.