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Water in passenger footwell - where's the leak?


Zoom Zoomin'
2011 CX-9 GT
Update: I pulled up the driver's side carpet and traced the leak. It is coming from behind the firewall, right in the center where the steering column is. I then found a plastic hose I had left on the windshield vents since the time I SeaFoam'd the engine back in 2009. Coincidentally, this is about the time the leak in the car started so I wonder if that plastic hose was blocking the water from draining out as it should.

I dried the carpets as much as I could last night and fortunately it's raining here again today. I'll check again tonight if the leak is still there.
"Great" thread. I've had a leak for over a year now on my '98 3rd Gen BJ. Thought it started when my windshield was replaced but recently had another windshield replacement and it still kept pooring. Same symptoms, same smell same location on the seams. However, my seams on the inside are still sealed but its pooring through the sealant. Going to pull the fender soon, i'm changing towels like crazy.

But i've found another leak on mine coming from a seam at the rear of the sound deadening. (borrowed the pic from 323 for indication)
Investigation starts.


So I dried the footwell last night and it was raining hard last night. There was substantially a lot of water from the seam-spot and little from the spot at the rear of the sound deadening. However there was another big puddle that instantly got my attention. It's on the gearbox side near the black plastic tunnel for the rear passengers airblower but also on the top left edge of the sound deadening. At this point I can only say "What the Deuce".

Thank god for this thread and you guys finding one of the sources! Thanks.

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New Caney TX
I stuffed an old t-shirt near the top edge of my carpet behind the blower thing until I get an urge to frustrate myself with figuring out how the hell to get at the source without being able to physically see it :(

Ripping out the dash seems like the only way to get at it...not fun in my opinion!
1993 miata
i ended up just loading a bunch of sealant where i thought my leak was coming from(only visible place) and im pretty sure i stopped it
We put some sealant in the seams that are behind the strut top when you open the hood. Looks like it stopped leaking at the place near the ecu.

But the water leaking from the bulge in the floor is not stopping (two left arrows on the picture I posted before. I didn't know water could defy gravity?
Its creeping up from under the metal plate on that bulge.

Its not coming from water on the road, it usually only happens when it slowly pours rain.

I have my carpet out for a while now until I found the solution. Looks damn ricey though :(
Mazdaspeed protege
Mine just started leaking about a week ago...SUX!!...i pulled the carpet up and it looks like the water is coming from behind the dash. I poured sum water down the right side fender and looked inside the car and water was working its way down next to the ecu cover...my next step is to take the fender cover out i guess...i have a absorbing rag i use to dry my car there and it seems to be working pritty well
My leak has once again begun.
Suprisingly it seems that the slower water pours on top of the car, the more it gets inside the car.
Rain gives more puddles in the footwell than when i'm washing the car with a high pressure cleaner.
Most of it comes from the corner at the firewall/ecu.

I'm going to take both fenders of soon, hell of a job but I want to know exactly where it comes from and how to stop it.

Not to mention that I have to de-leak the seam under the taillights, which is also leaking on the driversside (there's an official TSB of) and there's water coming in from the pressure-thingy in the boot. Hope to finally get it dry without all the towels!
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lolmsp lolms3
i think this is something worth taking a look at. take off your fender liners to see if there's a bunch of dirt/soil in there by the front of your sideskirt. might be holding water and making it's way into the car
I took off my fender on wednesday...hard to see anything that is not proper :(
Even behind the wiper cowl everything seems to be ok.

I took some pictures of the chassis with the fender off but my camera is at home right now.

One thing is for sure, nothing is clogged up. We also cleaned all drains and dirt by hand and an air compressor.
99% of the water drips of the car quickly but after a couple of minutes or a quarter of an hour you see some drops
on the inside.

Also the water comes in at 1/3 or half of the height of the firewall on the inside. And it's not coming from any fans, ac lines, wires, seals or rubbers, it's
really coming through the seams.

And on we go.
I worked at a rental car company for a number of years and have tracked down a number of leaks in brand new cars. From good size leaks that have filled up the foot wells to small pin holes in the seams of the car. And the only way to fix them is to try and narrow down first the direction of where the water is coming from. Water almost always pools up in the foot wells of the car so pulling the carpet up is always going to happen and is needed to be able to dry it out or you will get mold in the car. Then you need to start in one area running water on that area for a few minutes. Then move to another area until you can see water coming into the car and you just need to start tracking it down from there. Often times it only takes a few dabs of sealer to fix the leak but can take a few hours to find it.
Thanks Chris. We're indeed trying to narrow down the area. Unfortunately it is still very vague.
Three man strong pouring water, checking, sealing parts that could have been it but yet nothing.

Like I said before, spraying water with a hose doesn't give as much effect as rain does.

I left my camera at work so the chassis-pics still have to follow.

One thing I would like to know from all others, do you guys/girls use or have used a roof rack on the car?
Trying to figure what the origine is of the leak.


New Caney TX
Under each of the fenders is a drain from the windshield cowl under the wipers. They get crudded up easily and mine were nasty but now that they are cleared seems the cowl area is still allowing a small overflow of water somewhere. Area at the front of the sideskirts were cleared out too. Guess I'll be pulling back carpet soon and test specific areas. Just a matter of time before something electrical gets fried :(
2007 Mazdaspeed 6
Some people have tried flashlights from the opposite side of the floor sheet metal while dark to see if the welds have cracked. Good luck guys, I had the same on my trunk a while back and it was a pain in the neck!!!


I'm Back in 2010!
Thanks Chris. We're indeed trying to narrow down the area. Unfortunately it is still very vague.
Three man strong pouring water, checking, sealing parts that could have been it but yet nothing.

Like I said before, spraying water with a hose doesn't give as much effect as rain does.

I left my camera at work so the chassis-pics still have to follow.
I am willing to bet you have a cracked seam behind the corner/upper right side of your dash. Exactly where mine was. I was NOT able to repair mine without taking the dash out. I filled the crack as much as possible without taking the dash out, all it did was SLOW the leak. If you get time, pull the dash, then you'll be like OMG SMH. Easy as pie with dash out. Report back with updates....
2002 Mazda Protege ES 2.0L
Hey Everyone,

I just want to thank you all for taking the time to post all this info it's been very helpful. I recently bought an 02 protege and found out today after some heavy rain I've got some water problems.
Seems this has been a problem for a long time with this car because when I pulled back the carpet I found some serious rust on the floor. Most of this thread has talked about the cracked seam on the passenger side but I assume the same issue could occur on the driver side as well?



Msp 666 Aka Christine
2003.5 Mazdaspeed Protege
So i did my winshield and the car still smells funny. Guess the dash is my last resort. How hard is it to remove?
Is the carpet still wet? Only reason why it could smell.

My ultimate solution was the seam on the side at the chassis. It's behind the struttower and between the firewall. It's near the 'corner' where the firewall meets the chassis. I put my head on the valve cover, looked to the left and there was a tiny hole visible.
Resealed the seam there including the corner seams and voila...no more water.


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