Water intrusion

[Miker]

So when I got my 2005 in 2022 I found the floor on the passenger side to be damp. I cleaned out the cowl drains and remover the rubber snorkel from the bottom. I removed and sealed all the cowl clips. I also sealed the trim pieces that are above the windows. I thought that I had it sealed up good but after a few days of heavy rain I found that under my floor mat on the passenger side was again wet. I just took it for a drive and was shocked to see water droplets on the carpet coming out from the passenger kick panel.
I removed the panel and found this white piece that cannot be factory but looks to be there to keep water from entering the SJB. It looks like it works as there was still some water in it that would spill out forward when you hit the brakes. Is it from the factory?
I removed the seat and have a fan going to dry the matt. I pulled the passenger side windshield cowl and all looks well there. No debris at all where the cabin filter is and it is bone dry. The clips are all still sealed. Now that the seat is removed I will be able to get in there and watch to see where water is coming in hopefully when the wife hits it with a hose. Very frustrating!!!

 

[Miker]

So I did some searching and have seen that white piece on other SJBs so it appears it is factory although none were shaped like mine is. I do remember reading that there is a gromet under the inner fender that can leak or the grommet from the door wires although that one I can see and it looks solid. If I can't find this leak it is a deal breaker as the car sits outside unfortunately.
Any ideas what might be letting water in that area? I'm sure once I locate it it will be very apparent, but again beyond frustrating!

 

[fujifrench2k4]

This should help narrow down where water can leak in. I would also check your rocker molding area where it bolts to the fender. I had a build up of leaves that would allow water to leak in from below the smart junction box.

 

[Miker]

This should help narrow down where water can leak in. I would also check your rocker molding area where it bolts to the fender. I had a build up of leaves that would allow water to leak in from below the smart junction box.

I can't thank you enough!

 

[86GT351]

This should help narrow down where water can leak in. I would also check your rocker molding area where it bolts to the fender. I had a build up of leaves that would allow water to leak in from below the smart junction box.

Good info there.

 

[cavero]

Is that white piece a soft foam sheet? Mines had a sheet from when it was new that sits between the SJB and the panel cover, which I always assumed was to stop rattling

 

[Miker]

Is that white piece a soft foam sheet? Mines had a sheet from when it was new that sits between the SJB and the panel cover, which I always assumed was to stop rattling

Yes it is a foam piece. I don't think the way it is formed in the picture is the way it originally came from Ford. The water must be coming in directly above it as it was pooled in the foam and would run out forward when the brakes were applied.

 

[Miker]

Been out working on it. Had the wife spray around with the hose on the cowl, hood hinge area, window seal and the gap between the door and fender so as to hit the door wire grommet. Nothing leaked. I have the passenger seat out and I was laying on my back with a flash light watching for drips.
I had a thought that maybe water is getting into the cowl while driving and where I had it parked the car was leaning to the front and left. so any water in the cowl would pool to the passenger side.
In the TSB it says that a cowl water issue will leak down right above the SJB. It is definitely leaking above the SJB since there was water in that white foam that is formed into a bowl.
The TSB also says to inspect the pinch weld in front of the cowl clips especially the center support area. I did and this is what I found.

 

[Miker]

Looks like they skipped this area all together with seam sealant. It is slanted down and away from the cowl but when driving in the rain water could be forced up there I suppose.
I taped off the vents in the trunk and ran the blower on high non recirculate and sprayed the whole cowl area and the upper trim area above the windows with soapy water. Clips and seams and even that center section and got no bubbles. Not sure how much I buy into that though. I just remembered that I had the seat bolts out so air could have been exiting there. Dammit!

 

[Miker]

Just thought of this too. Yes the 2 seat bolts were out. But besides that the sill plate and kick panel were also off. The door looks like it seals against those surfaces so there was no way the interior was being pressurized with the fan running. So the absence of bubbles from spraying soapy water was meaningless. I'm going to put it all back together tomorrow except for the cowl covers and try the soap spray again.

 

[Miker]

So I put the car all back together except for the windshield cowl covers. I found the actual vents in the trunk behind the wheel wells. I would bet most do not even know that they are there. Taped them both off and sprayed the car down again with the blower running and no bubbles anywhere. I highly doubt the validity of that test on a 20 year old vehicle. Way too many avenues for the air to escape.
I sealed the gaps I found in the cowl by the center support with Dynaflex Ultra, the same stuff I used years ago on the cowl clips. I also sealed the top of the fixture that the cabin air filter fits in where it meets the body.
So really I didn't find anything that I know was leaking so now it is a waiting game until the next rainstorm comes.
In all my research on this I discovered that it is a fairly common issue in the S197 cars but also 2015 and later Mustangs as well. There is a pretty substantial recall on the later years for water intrusion causing electrical problems involving loss of exterior lights.

 

[JC SSP]

You don’t have to wait for a rainstorm, run it through a car wash…

 

[DieHarder]

Like JC says run it through a car wash with the passenger seat out and the carpet rolled up. Check for leaking at the front and rear of the door with a flashlight. In my case the upper window seals were leaking but I also had to seal the base of the windshield and pinch welds. So far, so good. Chasing leaks are a bitch but worth it in the long run. The TSB can help you narrow down likely areas at fault.

 

[asdrew]

You don’t have to wait for a rainstorm, run it through a car wash…

One bonus of the car wash method is when the blowers dry the car and pressurize it from the outside. On my convertibles, that'a when any discrepencies in how the top is closed show up.

 

[Ret]

You take your convertible through the automatic car wash? I've never done that figuring there is some wax residue that would get on my canvas top. So, instead I use the high-power wand and hand wash the car.

 

[asdrew]

Yes. No issues with the tops. I currently have 2 convertibles and 2 spare tops.

 

[Miker]

You don’t have to wait for a rainstorm, run it through a car wash…

I don't want to do that. Even if it leaked I wouldn't know where it was coming from it seems. I did wash it yesterday and no water got in. I can put my fingers in that bowl in the white foam by reaching in above the kick panel and it remained dry.

 

[Miker]

So after the unreal amount of rain we have had lately my carpet is again wet. I am going to pull the seat again and get the fan under the carpet to dry it out. I did notice this orange tube. That is the grommet that is under the glove box on the firewall. It is directly above where the carpet is getting wet. It doesn't look factory. Could this be my leak? Does anyone recognize this from their car?

 

[Miker]

Looks like from what I found that is a factory part so that's not the leak. I just pulled the seat and the insulation under the carpet is soaked in front of the seat and under the seat. The insulation that that is that is on the vertical panel where the passengers feet would rest is soaked. Beyond frustrated with this. None of the carpet feels wet so it seems the water is getting in under the carpet.
I guess my next step is removing the back seat side panel pulling the carpet all the way up and hitting it with a hose again. Maybe the trim piece above the window that I resealed didn't take.

What have you done to your mustang today?

Changed my alternator, By the way, new here and was wondering how does one go about posting a thread. I have a question regarding my fuse box.

www.s197forum.com

 

[GriffX]

I had water running through the indoor air filter, because these cowl drain...things....were clogged and after a rainstorm I vacuumed more than one gallon water out of my floor. That was fun......