Water leak under carpet - passenger side

I've been up and down tacomaworld forums and all over the web trying to find others with a similar water leak in to the passenger side of my tacoma - still no luck.
Some background......
Initially had water ingress on the top of the passenger side A pillar. The roof liner in that corner would get soaked and water would drip onto the floor mat. Looking at the forums, thought it would be a windshield so I had a new one installed. Still had the leak, took it back to the Windshield shop and they replaced it again, told me it is definitely not the windshield.

I took it to an Auto shop in town that does leak testing and they determined it was a faulty spot weld up in that corner. They sealed the weld with Beta Seal 1 urethane sealant. To do the job, they lifted the windshield and were able to replace it without requiring a new one.

Post repair, all is well until I start smelling a musty smell. I lift the mat to find the carpet and underlay are completely soaked. I lift the carpet to find that there is a missing body plug. Great, replace the plug, dry the carpet and all should be well.
Subsequent rain storms, checking the carpet, still dry.
Park at work, lots of rain, go out to see that if the carpet is still dry......to my dismay, carpet/underlay in very bottom right side of cab is wet! Remove trim and glove box, can see water on top of connectors that are behind the kick panel on the lower right side. Just above the connectors is an airbag sensor that has some foam on it, it's wet and carpet above this sensor is also wet.

Take truck home, remove cowl cover and soak all over the truck with the hose....could not make it leak!

Water is not coming in via AC drain.
Water is not coming in through air cabin filter and fan.
No drains that I can see are clogged.
Windshield looks like it's well sealed and could not get it to leak soaking all over with the hose

I would love to see a diagram, pictures or exploded view of the 2nd gen. tacoma without the passenger side front fender. I'm curious about the lower cowl seam that is the subject of a TSB that I came across.

When I get time I will post some pictures. I appreciate any feedback and in the meantime, I will be trying to re-create the problem.

 

I haven't had this problem with my Tacoma, but my old Colorado leaked like a sieve from the 3rd brake light on the cab. And it threw me off for a long time because the water would always settle at the front floor boards, not the back, so I always suspected it was something at the front like the cowl or windshield too. Maybe check the seal on that brake light when you get a chance. Once I figured that out I fixed it in 5 minutes with some of the double-sided foam tape stuff.

 

You don't have any aftermarket roof rack or light bar brackets on the roof that could be leaking from a bad install or seals around drilled holes failing do you?

 

This may not help but someone I know with an explorer had a similar problem with passenger side floor mat getting wet. Turned out to be leaking from the heater core, or some competent of the heating system. Not sure specifically where these are located on the tacoma but could try running your heat to see if that recreates the problem. If nothing then you can check that off the list of possibilities.

 

Also check around your door seals. Look up how to take your A Pillar off and check for any leaks underneath. Also a hose isn't going to have the same pressure as heavy rain under highway speeds. Take it to the carwash or use a pressure washer (DO NOT PUT THE JET DIRECTLY ON THE PAINT, YOU WILL CHIP IT). Just blast it from a distance and see what happens. My buddy had a Jeep Cherokee and we found his door seals were bad when we pressure washed it and water started coming down the a pillar. My grand am leaked from the sun roof and door seals too, I used to keep a towel in my floorboards just for that.

 

Also, next time you have a heavy storm coming in, turn your recirculation on before you stop the truck, just to make 100% sure its not coming in through the air ducts.

Its a good way to keep mice out of your blower motor too apparently.

 

No roof rack or after market mods at all on this tacoma, all is stock. I'm fairly positive that it's not related to heating/cooling. I drove to work in a light rain, no water ingress. Rains heavily during the morning as the vehicle is parked and when I checked at lunch, could see small amount of water pooled on the floor at the front right, and could see the water on top of the connectors that are behind the trim. Putting my hand up behind the where the glove box is (have everything removed), can feel the carpet is wet. I've removed the A pillar trim piece and did not see any water.

There is a slight deformation of the door seal on the passenger side close to the level of the mirror. I will tape it up to see if this fixes it, however, don't see how water is getting in as it should drain behind the pillar.

Thanks for the suggestions!

 

Try closing the door on a dollar bill and drag it around to see if it’s tight

 

I had a similar issue, wound up being a clog in the drain inside door sill. Open your door and look at the inside of the door sill at the bottom under the hinge. There is a small rubber flap, pull out a little and make sure its cleared. I will snap a photo in a min for ya. Good luck

 

Feel your pain, had this on my wifes pilot. was able to locate the leak by removing trim and carpet then running a hose on the roof and down the windshield and sitting in the cabin hoping to see where it was originating from. Have you tried running water , sitting in the cabin and then checking?

 

Have you maintained your rubber door seals? They are they for a reason. If the rubber dries out, they lose there function as a door seal.

 

Theres also a rubber grommet behind passenger kick panel. Looks almost like a bouncie ball with a wire in it. On my 06 it came loose and leaked. Sometimes its a real PITA to find a leak because water travels. If you do find the problem, post it up so others with this issue can be helped.