Water Thru Cabin Air Intake - My Solution

It happened again Tuesday, so I decided to finally attack this problem.

Four or Five years ago on a heavily raining day, my wife got in my truck at the park-n-ride to borrow it for awhile. She turned on the fan and water came shooting out the defrost vents. Then she found a very large puddle on the passenger floor mat (costco mats which hold the water). Dealer tested it for the TSB related to water on the passenger floor area and hosed it down real good with no luck of reproducing it.

Years go by and it never happened again...until this Tuesday. So I was wondering if something was done incorrectly when I got the new windshield a couple of months ago (although I doubted it since it happened once before). Still, there were people claiming that the wipers and cowl should be removed when the windshield is replaced. That's a wrong assumption and I'll show you why in the pictures. It's actually better if they don't remove the cowl.

So here's a shot of the cabin air intake box with the cowl removed (you can just seem my DIY washable cabin air filter in the pic):


The Cowl has a channel in it that the glass slides into just above the cabin air intake box. Thus the need to leave the cowl in place when replacing the windshield. This is a perfect guide to ensure they put the glass in the correct position (height-wise) so you don't have trouble re-installing the cowl or leaving too much of a gap for water intrusion purposes.



Below is a closeup of that channel on the cowl that slips under the glass. Notice it has tabs that slide under the glass. This way the glass sits against the top of the cowl leaving a channel below it for water evacuation away from the cabin air intake. The water then drains off the ends. However, this is where there are a couple of faults in the design. I'll get into that after the picture.



Okay, so there's two problems with this design. One is that at the end of the channel, water could run down and back underneath onto another lip below the channel back toward the cabin air intake box. There's a vertical fin that's part of the cowl mold that would stop the water from continuing on, but that fin still sits about 2 inches too far toward the intake box. That could cause water to drip into the box.

The other problem is what I believe some of us have suffered from. Depending on the slope you're parked on, this channel may not be big enough and it doesn't have a back lip (windshield side) to stop the water from pouring over the edge anywhere along it during a heavy downpour (or if you get debris in the channel, you're screwed). Notice how open the channel is in the pictures. I think this is the problem I've suffered from twice now. Both days there were major downpours from thunderstorms. My guess is that it just can't handle it.

My solution? Install a piece of flashing directly over the cabin air intake that will always direct the water away from it. I shouldn't have any more leaks now.

 

I have never had any water get into my cabin from rain, but if I ever do I will come back and look at your pictures and see if I can figure out what you are saying.

 

What I have encountered in certain vehicles is that the 'drain' for the cowl area where the cabin filter intake is located gets clogged up (sometimes even slightly) with debris (leaves, tree seed spinners, pine needles, etc..) & cannot evacuate water fast enough in a heavy rain, or in melting snow conditions.

Ford Taurus's are notorious for this problem.. & although Ford has issued a cowl reseal update to address this problem, if you don't clear the drain, the re-seal is completely ineffective..

 

I can see that could be the case. But the intake box was dry except in the areas where it would have dripped off the cowl. There were distinct "spots" where it dripped in, rather than run over the sides. So I know I'm on the right track.

 

Seems like most everyone that has had this issue has had a windshield replaced.

 

Not me. Happened within the first year of ownership and the first glass replacement was just a couple months ago (and I know it was the factory glass in that first instance because I had the windshield buzz (never fixed by the TSB) from the factory that I just got fixed with my windshield replacement recently.

I've parked out there with the downpour many times over the years and it only did it twice...both times I was parked on a specific slope at the park-n-ride that I think may have attributed to the angle of the channel allowing water to run in instead of draining away properly. Either way, it's fixed now.

 

Yea I was just sayin quite a few people who have had this problem have had replacement windshields

 

Any more problems since installing the flashing? I think I have the same problem on my '10

 

None since. With the flashing, there's no way I'll have the same problem ever again. But before assuming that is your problem, make sure the drains in the cowl are clear (use a hose and see if it drains at each fender properly). If the drains are clear, then this probably was your problem.

 

Went out and checked mine this morning. Drains are clear, but I did have water on both the driver's side and passenger side under the floor mats. I went on ahead and installed the flashing as you did, but before I removed the cowl I did notice the weatherstripping on the cowl was not sealed up against the windshield. Here's the pic, the flashing will have to do for right now until I can get it into the dealer. Can't figure out how I am getting water on the driver's side as well.

 

Are you sure the water came in through the cabin air intake? Was your cabin filter wet? A dry cabin filter or having water on the driver's side is usually an indication of a different leak. Although from your pic of the cowl seal against the windshield, that's almost a guarantee of water into the cabin air intake hole.

 

Filter was dry, but it has been a while since it has rained. Maybe the filter has dryed out since then.

 

Had water on my floormat this morning after a heavy rain. Now when you say flashing, is that just a piece of sheet metal bent over the part under the cowl?

 

Thanks!

 

Yep, hardware store has flashing in rolls in various widths. I just had them cut me a foot's worth of the wide stuff then trimmed it to my specifications.

 

sub

 

Hi,
Great post. What did you use so that it does not flap/move or rattle around in there??

I cleaned my cowl and can see the gap. May need new cowl-seal?

 

I just used construction adhesive on both edges (sides facing windshield and engine). I wasn't sure it would last, but it's been 4 years and has held. And not a drop of water in the intake since.

 

and some guys are redirecting the air intake into the cowel, over getting a snorkel!

 

Silly question but I'm getting pine needles to my cabin air filter, can someone explain where the cabin intake is? Been looking under the hood but can't find anything that looks like ^this