Water under passenger mat

I will look into that tonight. It rained all night and I just checked the carpet, it's dry. So I doubt it is the windshield now

 

I looked last night and I used dip stick to unplug the nipple coming out into the engine bay and it was clear. Nothing came out. I looked under the glove box and it looks like there was some type of sealant (milky color) used on the rubber hose going into the HVAC box and thru firewall.

I just ordered these:
87128-08030 Grommet
88539-04020 Hose Drain

 

Here are a few pics after I cleaned the old sealant off the grommet. Someone was in there before for some reason, I ended up cleaning everything and putting a paper towel under the grommet to see if water comes. New parts be in Tues/Wed. So basically I just remove the grommet/nipple from inside the engine bay and then reach under the glove box and take the hose off?

 

one additional minor step... take the blower motor out, really simple, 3 - 10mm head bolts and an electrical lead, then with your hand feel inside the evaporator box and see if there are leaves or other debris in there.

 

Is the blower motor the black box in the last picture? Thank you

 

The blower motor is the round black unit on the right, in the first picture.

 

Yep. This was my culprit. Fixed and no issue now. Good luck OP

 

The piece behind the blue/red wires? The black box with the drain tube coming out is the evap box right?

 

Correct on both accounts.

 

I inherited a wet passenger side carpet in my 99 Tacoma. My only advice is to find the leak as soon as possible because a wet climate ( Seattle area) will become ruinous to your carpet- it will start to mildew and then it will start to stink. I have had to remove the entire carpet because it soaks up water like a sponge. And there is little opportunity to dry it out. The water inside the cab will condense on the windows, then will fall back onto the carpet and upholstery. Toyota had issued a "repair" notice but that didn't fix mine. ( I see if I can find it) I just had a new windshield put in. Slowly but surely I will make this ride pretty again. Good luck.

 

What side of the grommet faces out toward the engine (pic 1 or 2)?

 

Well I installed the new rubber pieces and I checked again with a weed wacker line and nothing seemed to be clogged up in the evap and I felt no water whatsoever and none on the weed line either. I took the passenger side seat out and lifted the carpet and have both doors open with a fan on full blast. The carpet in not wet, just the padding. It's actually damp in a 10" diameter. Maybe the guy I bought it from spilled something and with the floor mat on top it never got the chance to dry and when I got it I put a rubber floor mat there. Can't think of any other places it would come from and the border of the carpet is dry and the border of the padding is dry too

 

Is your current drain plug and grommet still in the firewall? Can you figure out orientation based on that?

Mine is concave on the interior side of the firewall... the pic you posted looks similar. Hard to tell with the pics above if the grommet is concave on one side or the other.

 

I put the new grommet and drain hose in and the old pieces looked fine to me (but for $5 it's worth the piece of mind). It's the same

 

Good deal. Probably doesn't solve your leak issue but like you said, it's piece of mind.

Was your evaporator box filled with water? I can't remember.

 

Zero water...seemed dry as a bone. I inserted a weed trimmer line and there was nothing on that when I was going back an forth

 

Has the weather permitted a hose test? Either the windshield, firewall grommets or the floor drain plug? The latter is located right in the middle of the passenger side floorboard.

Photo courtesy of @SilverGhost

 

The floor drain plugs are in solid condition...Are the firewall grommets easy to find? I will do a hose test later today

 

Post #19 has a picture of the firewall grommet on the passenger side.

 

I'll check that in 5 minutes