Passenger-side water leak

It's raining tonight and I don't have the carpet installed in my car so I was able to observe a small water leak in action on the passenger side of my P5. The leak is in the right corner of the cabin, near the floor. The water seems to come out of nowhere, it's kinda weird. Hopefully I'll be able to get a better look tomorrow in daylight.

I'm assuming this has something to do with a clogged A/C drain, right? I've looked twice on the firewall for the drain but haven't seen it, can someone tell me exactly where it is?

Is this it?
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Just to make sure, the fresh air intake uses the same drain as the A/C evaporator, right?
 
It stopped raining and the leak stopped. So I went out with a bucket of water and poured it on the fresh air intake area. Sure enough, the leak started again.

I moved some wires out of the way to get a better look at where it's coming from and it appears to be coming from higher up on the firewall. Behind this rubber mat:
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It's been going on for a while because that mat smells awful...
 
True I don't blame you. What if you run AC for a good amount of time and try lookin for it that way? See if with the AC on if water is comin from one particular spot
 
So it's not a problem with the A/C drain. I finally found it, it's a stubby plastic tube sticking out of the firewall about 1cm. The tube is located near the bottom of the firewall on the passenger side right above the steering rack. It was hard to find because it was obscured by the power steering lines.

The easiest way to blow it out is to shove a tube with an outer diameter of 5/16" in the drain then attach your compressor blower attachment to that. There isn't enough space to fit your hand and the blower attachment.

I took justanothermp5's advice and got under the car with the A/C running to see if the drain is working. It definitely was, today is super humid and water was definitely dripping out of there.

Sadly that didn't fix the in-cabin leak, the water is still coming in :(
 
I'll just share my experience here...I had a leak under the dash, but the water was coming in through the edge of the windshield at the A pillar. I figured it out by using a hose to pour water along the edges of my windshield. I removed the A pillar trim and could see it running down. Safelite sealed it for $50 and it hasn't been a problem since.

You could easily be getting a leak around the windshield...they run so many different places that it's hard to trace them back without doing what I did. Hope that helps!
 
Is the water coming in while the AC is on?

Nope, it has nothing to do with the A/C.

I'll just share my experience here...I had a leak under the dash, but the water was coming in through the edge of the windshield at the A pillar. I figured it out by using a hose to pour water along the edges of my windshield. I removed the A pillar trim and could see it running down. Safelite sealed it for $50 and it hasn't been a problem since.

You could easily be getting a leak around the windshield...they run so many different places that it's hard to trace them back without doing what I did. Hope that helps!

I'll check that out, thanks!
 

I don't, but thanks for the link.

I ruled-out the window seal by removing the "Cowl Grill" and pouring water directly into the firewall gap. It still leaks through...
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Even with the cowl grill removed you can't see much. Does anyone know if I'd be able to see more by removing the fender? I don't want to remove the bumper and mud guard for nothing.
 
I poured the water all along the windshield edge, not just along the bottom...removing the A pillar trim inside the car. I looked for leaks that way. My leak was along the vertical edge of the windshield about 3/4 of the way up...it would run along the A pillar inside the car all the way down to the footwell, where it leaked off of a dash piece.
 
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I poured the water all along the window edge, not just along the bottom...removing the A pillar trim inside the car. I looked for leaks that way. My leak was along the vertical edge of the window about 3/4 of the way up...it would run along the A pillar inside the car all the way down to the footwell, where it leaked off of a dash piece.

It's definitely not from the window for me. I still had the leak even when water wasn't ever coming into contact with the window :(
 
Any chance you looked through here?

http://www.mazdas247.com/forum/showthread.php?123757400-Water-in-passenger-footwell-where-s-the-leak

Im hunting down a similar problem right now... Looks like that seam could be a part of the problem.

Damn, there's a lot of good info in that thread, thanks! I'll take off my passenger-side fender this weekend and see if there's anything that can be sealed-up on that end.

This evening I tried removing the blower motor housing but that's impossible if you don't first remove the A/C evaporator housing :(

I also did more tests. I set a running hose on top of my cowl grill on the passenger side and shoved my hand as far as possible up behind the insulation in the passenger-side corner of the footwell. I made it to the point where the firewall starts to run horizontally and felt a drip-drip-drip coming from somewhere higher up. This is getting rather frustrating.
 
Yesterday I removed the passenger-side fender but sadly that didn't help, the leak comes from higher up than what's visible with the fender removed. The only way I'm going to find this leak is by removing the dash. And I really don't want to do that.

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^If anyone cares, this is what you see with the passenger-side fender removed.
 
I ended up removing the dash, the weather was perfect for doing that sort of work. More importantly, I found the leak!

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It's in the worst possible location, where the arrow points you have to shove your hand in as far as possible and feel upwards. There was a line of rust in there which was oxidized enough to start letting water through. I did my best to seal it with polyurethane roof sealer but its in such an awkward place I can't tell if I did a good job. Time will tell...

If I removed the A/C evaporator and the blower housing I'd be able to see the hole properly but I didn't want to drain my A/C refrigerant.
 
My fix didn't work, it's still leaking :(

I guess I'm just going to have to live with it because there's no way in hell I'm removing the A/C evaporator.
 
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