Or the AC drain is plugged and depending on the car parked on a slope the water spills out onto the carpet

 

"Keep us posted"

After all that worry.....

A few days ago, I had time to go out and look that car over. I was looking at my windshield wipers when I noticed that the lip of the cowl that was sealed to the windshield had some major vertical splits in it and I could easily pull it away from the glass in spots.

I decided to just temporarily stick some duct tape on those areas for the time being. The next day, came a pretty good thunderstorm and I thought to myself, "crap, now I gotta soak that floor dry. No I didn't. It was still a tad damp from previous floodings, but no new water. I am guessing I need to use a black silicone adhesive sealant to get it reattached. Could that have been it?

 

Thanks man. I just noticed that the very top of the cowl, that black strip that is sealed against the windshield has splits in it and I can actually lift it away from the glass. I duct taped it for the time being, and yesterday had a pretty good storm. No leaks or wet floor. I am guessing I need to get some silicone adhesive and reseal the top part of that cowl.

 

That black part of the cowl is not supposed to be sealed to the windshield. It just covers the cowl area.

 

Windshield leak. It happens, moreso with replacement glass.

 

I have those cracks and my car has never been anything but bone dry. It's something else. If taping over the cracks helped, that's a clew as to where the problem is, not an answer.

 

I have essentially the same facts as OP, except no cracks. Mechanics have twice now cleaned that drain but it comes back, quickly, a virtual cloudburst of ice cold water from the blower onto the passenger side well after maybe 50 miles. I sense the shop just wishes I would go away.

 

What facts are "essentially the same"? If everything is the same except yours is a 2006 model the problem is the butyl patch.

 

Oops. Sorry, I thought I put 2009 in the profile. My mechanic went on and on about what a terrible design the A/C drain is, but felt that with regular cleaning I'd be ok. That lasted maybe 100 miles. Again, the water is very cold, so I don't suspect door or window seals.

I just inherited it from my uncle, with 40K on it, and gave it to my teenage son.

 

The drain, on the engine compartment firewall, looks like this inside.




I remember one member cut the fins out to reduce the blockage.

You probably have muck (moldy dust) in the drip pan that keeps clogging the drain.