After doing some digging on here and out at the car I figure its time for opinions.

Finding a lot of water (like a pool) in the front and rear passenger floorboard. This seems to happen when the car is sitting after it has rained or snowed. It’s not coolant.

I dug around searching for the source when it thawed out last week...couldn’t find a path to the floor pouring pitcher after pitcher on the doors and windshield.

Confirmed that the duck lips are clean, or at least nothing came off in my hands. Ceiling is dry, and I can’t get the doors to leak when I try to replicate it.

What confuses me is that the water is both ahead and behind the hump under the passenger seat. Which implies to me that either the doors are letting in water in some way I can’t replicate, or water is running down the ducting to the rear passenger floorboard. I did notice that the nav screen didn’t turn on a couple weeks ago after a hard rain, so I am leaning towards water coming in under the windshield somehow and down that ducting.

Thanks for any additional pointers!

 

Possible and common leak points:

Sunroof:
There are tubes in each corner of the sunroof tray -- get a replacement speedo cable from the Autozone HELP! section and run it from the sunroof down until it pops out at the other end.

Roof rack rails:
Also check the roof rails (where the roof rack clips are), they can sometimes leak as well, but are easily fixed with a dab of windshield silicone. The giveaway for the latter is moisture near the windshield, where the sunroof bolts in. You may have to remove or drop the headliner to see it clearly.

Cowl:
The cowl and intake fan area can get clogged with leaves, twigs, and other detritus. Pull the cowl and clean/vacuum out this area. Also pull (maybe replace if never done) the cabin air filters, from behind the glove box door. Vacuum out the filter location before installing new filters. Unlikely if water is moving beyond the front footwell

Windshield seal:
This seal can fail, leading to isolated leaks into the car. Look for water that is coming in under the dash. Unlikely if water is moving beyond the front footwell.

Door seals:
The door seals can be damaged and allow moisture into the cabin. Check for areas not holding tightly to body, that are crushed, cut, or torn.

 

Thanks for the info, apologies for never responding.

Figured I would update this; I still haven’t figured it out.

I parked the car outside for a light rain last week and sure enough was left with a small pool in the Front Passenger Footwell. Not once have I found water on the Driver’s side.

Here is everything I have looked at:
Sunroof:
- I’ve cleaned and fished a cable down each drain. I bottom out the front drains with the cable at the same point, several feet down. Is assume this is normal?
- Poured tons or water into drains, and nothing seems to fall into floor.
Cowl:
- “Duck Lips” checked, with no obvious plug
- I assumed this was the spot, pulled everything I could manage until I hit the plastic underside panel that appears to require the windshield to be removed to pull.
- Again, tons of water applied here but to no avail.
Door and Seals
- Seals seem fine Tons of water with a hose over doors again with no leaks
- Pulled Doorcard to see if strange speaker grill leak was the suspect. Not seeing any signs of water under there.

So short of having the windshield pulled and resealed, I’m not sure where else to go next other than to gut the interior in hopes of finding the leak.

Just confused as to why I can’t replicate it.

 

Just spitballing idea's but if you have a camera to setup maybe you can put it in your car next rain so you can maybe catch a drip direction or location to try and narrow it down?

Funny thing I saw on mythbusters gave me an idea too, placing tissue paper around the car might help narrow it to a region, since it wrinkles when wet and will probably pick up dirt and discolor from the rain water. I was originally thinking ph strips since I have some around the house, but I'm a teacher so I have lots of odd **** around the house.

When I was chasing down a leak in my trunk, i found that testing with a hose didn't put water on it long enough to simulate rain, sometimes I guess the water gets in through capillary action rather than force and it takes a while for enough to get through to actually be felt or seen?

 

I had the same problem this week on the driver’s side footwell.

Pulled the windshield cowling off and cleaned out the drain holes and it seems to be fixed (thanks 200).

The long term water sounds like a good idea. Instead of a hose try a sprinkler with lots of flow for a longer timeframe. Will be closer to what a rainstorm does.

Good luck cause this is frustrating.

 

Thanks for the ideas guys. Will see if I can set something up to better mimic the rain.

Agreed that it is frustrating hahaha.

 

Me and my slow progress!

Took the suggestion of using color changing tape for water leaks. The stuff I got turns pink/red when wet. We’ve had a nasty few days of cold and light rain here in Ohio so it was perfect for this test.

I may have finally found at least the zone that the water is entering from.





Water appears to be coming straight out of the hat section brkt on the inside of the fender.

Kind of a strange spot, so my guess is the cowl or fender is finding a way to fling water onto this body face. Will get the car in the garage and do some removal again.

 

I had that problem. I cleaned the rubber around the sunroof and the area it contacted with alcohol and rubbed mineral oil on the rubber afterwards to soften it up some. It’s been dry since and it has rained a fair bit since.

 

regular mineral oil from the pharmacy/drug store?

 

Yes, from a drug store. I can't guarantee the long term effects tho, so use at your own risk. Make sure you use 99% alcohol.

 

You’ve had water on the floor? Or coming out of the hat section I am seeing?

I’d just be surprised if it was my sunroof, my drains seem clean and I would expect some water damage to the headliner.

Anyways, glad your solution fixed your problem, this crap is annoying.

 

Update on this; car has sat outside all day in the rain and the floorboard is dry!

Solution: Don’t be an idiot like me and seriously check your sunroof drains.

I previously had ran a bunch of water down the drains, confirmed they were flowing. Threw a snake down each to make sure they were clear. What I didn’t do was fully look at the way it seals. Thus this took way longer than it needed to.

So if you yank the fender off and look through the “port holes” in the unibody you will find your sunroof drain. Yes, it is halfway up the fender like the service manual shows.



When I first looked here I just made sure that it was draining. But if you look closely the “clipping” features actually extend through the unibody to you guessed it; the interior. The other side of the drain is a fender washer like flange that I assume had a gasket on it before.

My gasket must have disintegrated as this was just hard plastic to unibody, and with the small slits of the clips...just enough surface area for water to drip back down the interior wall into the floorboard below.

So my solution was a cut to fit faucet seal and a little bit of weather seal goop on the joint for good measure.

The hard part here is that reaching this required pulling the dash out of the way.


Now, as for why the water took so long to the floorboard; there is a lot of insulation right up against this part that I couldn’t see before. Therefore it has to saturate and then drip from that first...leak was immediate with the insulation pulled back.

Frankly Mazda could have prevented this from even being a thing by separating the drain line of the exit from its clipping features, but that must have cost more than a gasket.

So! Problem seems to be solved! I’m an idiot (queue Team popping in to reiterate that). Be smarter than I am hahaha