I have a 2001 Cherokee Sport and there's an interior water leak from the passenger side air handling unit when it rains. I removed the windshield wiper cowl and poured water on the passenger side under the cowl cover and that caused more water to come in. I also disassembled some of the dash board and the windshield seal is nice and dry. The drain on the air unit doesn't seem to be plugged as I am getting condensed water drainage when the AC is on in humid weather, but then again it may be that is a lot less flow than what occurs during a rain event. Any one have any thoughts?

 

There is a known problem under the windshield wiper cowl. I can't quite remember if its a seal or gasket but something in there gets old and allows water in. Some people cut a square on the passenger side and seal the problem or make a "dam" on the driver side. Check it out on Google shoukd be found easily

 

Sure its not from the door or door window seal or even up higher like the luggage rack?