05GTJOSH

I had the same problem and it turned out to be a plug that was clogged behind my engine on the wall. I unclogged it and the leak went away.

ford4v429

that would be one of these:


but those tend to cause major pooling in the front passenger foot well first, as the backups run over the blower inlet and down the wire harness. My drivers side plugged and still flooded only the passenger side floor- but that may vary depending upon how well the cowl caulking was applied at assembly. my 09 rear looked great, my 06 drivers side rear was completely missed around the shock mount seams- all the caulking/sealer was in a bead 1/4" from the joints... good help is hard to find

edit- heres a link to my old sealing thread, but somehow the pics went away?
https://themustangsource.com/f637/yo...ur-car-428745/

might still be some stuff of interest to folks in there...

FordService

Glad to learn this was handled for you, ageless1! Now, your CSM will take care of you. Have a good one!

Deysha

05RedGT

We had some heavy rain the other day and my passenger floorboard was wet again. Checked the cowl drain by the cabin air filter and it was clear. Checked the driver's side cowl drain and it was completely clogged. Pulled the rubber drain boot out and cleared it. Hope that takes care of the water leak issue for now.

Pony07

Yeah, those stupid robot welders. Not much better than when humans did the welding.....

ford4v429

wasnt weld, just seam sealer caulking- and from the irregularity of the beads, dont think it was a automation issue

ageless1

It turned out to be the butyl rubber windshield seal at the bottom of the glass, passenger side. It only leaked when parked uphill (I park uphill) and while driving. Ford got it fixed for me when it was in and I've had no problems since. Just an update, sorry for the delay.

FordService

Thank you for the update, ageless1!

Deysha

Cowboy72

I just bought a 14 and haven't even made the first payment yet either and its already been in the shop twice now. When I bought it there was something on the windshield that when it rained it gave be 2 different views of driving and when light hit it you could not see out of the windshield. They tried to fix it and it made it worse. After arguing with them they finally agreed to put a new windshield in the car. Where I live there are no trees and at my job no trees. When it rains my passenger door you can hear water slushing around. I have checked the drains and nothing in there. Also you can hear water slushing around in the rear quarter. Last week we had bad weather and you could hear something banging in the back it was the ice. The dealer finally admitted he heard it as well. They don't know where its coming from and act like they have never heard of this issue.

ford4v429

my 06 sits outside, been parked since salt came out- well it hit 50 yesterday and rained- clean roads! took it out tonight, windows fogged up...uh-oh.
checked passenger floor, soaked again...
I left the rubber drains out a couple yrs ago, checked, and the cowl/drain are is clean- zero debris at all, so it didnt come in there...I redid the window trim gaskets a few years ago when they were squirming out by the mirrors, and leaking in bad at the carwash, they still look fine... checked the plastic inserts the cowl cover plugs into- the cheep foam 'pads' behind them, well of the 5 inserts, 4 had the pads squished out, plastic plugs were loose as hell, mold/algae all around the two outboard ones think they were the leakers most likely- surely part of it at least.

got the kickpanel/door threshold, carpet/toeboard pad folded up, rear seats down, dehumidifier sitting inside the car... opened the trunk, its so freakin damp inside the inside of the trunk is sweating like a pop can in july

going back out to take the wipers off and remove the drivers cowl cover, surely the same crap plastic insert/seal issue will be over there too.. will clean up all ten or however and put them back in with silicone or maybe automotive 'goop'... so stupid the added these punched hole inserts over the hollow part of the cowl- a little TINY bit of forethought, they coulda designed so they were outside the sealed area and these stupid freaking cowl leaks would have had ten less spots to fail... swear its planned obsolescence.

somewhere maybe in this thread someone wrote a perfect quote -
"50 years later, Ford still cant build a mustang cowl that dont leak" or something along those lines... really a dumb problem that almost had to be designed in... with all the urethane/sealer/seals, WHY IN THE HECK WOULD THEY SNAP 10 PLASTIC INSERTS THRU THE COWL AT THE BASE/WETTEST PART??? I swear, its designed to fail 5-10 yrs out in a way quiet and out of sight so you wont know till problems pop up.

should mention a couple other things I did-

1) the SJB gets rained on if the window molding weatherstriping fails- the plastic snaps thru holes in the A-pillar, and the foam is all that keeps water from getting to the clip/hole, which then is effectively a downspout above the SJB... I flipped the foam out from behind the harnesses, it now acts like a unmbrella- if those fail again(I used pretty good/thiker stuff- snapped in REAL tight, shouldnt come out again) at least the flood will only get the carpet.
2) the SJB also gets soaked if (no- WHEN) the cowl drains underhood plug up, or these stupid snap in pieces leak, the water runs thru the plenum, down the wire harness to the plugs on the SJB, as everything slopes downward slightly from the center console area...I lifted the harness up as far as possible on the outboard side, simply taped them to the floor with ductape- this creates a slight 'drip loop' towards the center, now if it leaks thru the cowl, water just follows the harness halfway, then drips off/soaks carpet, not SJB plugs

note- if your carpet ever feels wet, it will basically never dry unless you pop the threshold/kick panel(they pull right off) and lift the carpet, then fold the plastic/jute toeboard pad up- it can be used to 'prop up' the carpet, allowing air to circulate under that non-breathable plastic toeboard cover, and the carpet/floor too...otherwise, the padding behind that solid plastic will never ever dry out... padding has gotta be exposed to evaporate... I'll edit/add some pics in a bit of the stupid inserts and the mickey-mouse water damage reducing things i did to mine... no one will ever see them, and they shouldnt be needed- but jeez, these cowls are a pathetic design- or a brilliantly evil way to make sure they dont last forever...

Gato0126

Here it is 2017 and my 2014 has the water problems. I found the leaf traps under the hood were clogged. Unfortunately, my car is not garage kept and parked under a Crepe Myrtle. Lots of small leaves filled all the rubber traps during heavy rains damaging my cabin air filter where the water got through flooding the passenger floor. Cleaned out all the traps and also removed a plug in the driver's rear fender in the trunk and two small plugs in the corner of each door as well.