I have poured water in there and it winds up on the ground behind the front tires pretty quickly. I don't remember hearing a suction sound but I did pour about a gallon of water in less than a minute and it drained pretty much right away.

 

You can have a small hole and water will still move quickly, it is the amount of water that moves that is important. Mine was doing the same thing. i poured water into mine, it drained and i thought all was well. it wasn't until I exhausted every other issue, when i decided to find the exit ports of the tubes and see how it was designed. The exit ports are actually under the wipers, so the hood piece with the vent and wipers have to come up. After finding the ports, i stuck a rod in them to see how deep they were. Turns out they turn a 90 degree from the firewall in order to run the drain hose to and up the front pillars. That 90 prevents any string or wire to get past that point when trying to clear the line. And if you shoot air in from the top, the debris further pack into the 90 degree elbow. So what i did, was i pigged the line with some soft packing foam. I put a piece of the foam into exit port and shot some air to it. The foam was able to make its way to the other end of the line and ended up pushing a piece of stick out with it. So the water was able to drain around the stick, but not fast enough to keep the catch pan empty. i have no water for 3 years now.

 

Oddly enough it has a rained twice now and no water whatsoever. I don't know if it is the angle that the truck was parked at. (It was previously parked on a slope so the right side was higher.) Or if maybe the water that I found before had been there from before I sealed the roof lights. Either way I am going to set up a hose and do some testing as soon as I get a chance.

 

Do you experience water on the passenger floor when you have been running the air conditioner or the defroster? The drain hose from the condenser under the dash could be clogged. That happened on one of my pickup trucks.

 

Good question! I'll look into that!

 

I had a similar leak. I fixed it by getting glass adhesive and putting it on the front windshield - lower several inches - I pulled the rubber back - just barely enough to get the silicone adhesive in there, then I taped the windshield and rubber in place for several hours, then removed the tape and trimmed the excess adhesive. On the maintenance side, I went ahead and pulled back the weather stripping on all of my doors - gave them all a good clean, then added liquid rubber to a few sections. Additionally I got a step ladder, unscrewed all my roof lights, cleaned everything real good and resealed them with silicone. I also wiped down all of the rubber components with a good protective coating - something I use for interior and exterior plastics and rubber.

 

Did you put the packing foam on the top of the lines?

 

Did you get to the end of tubes from inside or outside?

 

The foam was used to push the debris out and to scrub the hose walls. I used a piece just big enough to fit into the exit port of the drain, and used compressed air to push the foam back up the line.

 

Both front and rear drain hoses exit to the outside of the vehicle. The front drain ports are located behind the wiper control arms, and the rear are behind the fender wells. you can pour water into them from the sunroof to better help locate where they are.