Water leaking onto passenger floorboard .... need help!

Hey guys,

So when I was vacuuming out my taco this past weekend I noticed the passenger carpet was a bit damp under the rubber mats I have. I pulled up the carpet today (very rainy) and noticed water dripping from this area towards the firewall. Any ideas where the leak could be and what I need to do to fix it?

 

First check to see that the AC evaporator drain hose is not clogged as described in this thread.

https://www.tacomaworld.com/threads/where-is-the-ac-evaporation-drain-located.232099/

If the problem is not solved by clearing the drain hose, there is a lengthy thread on the cowl leak problem below.

Note: There is information on a TSB in the thread with information from some of us who have dealt with the issue.

https://www.tacomaworld.com/threads/passenger-floor-board-leak-fix.432290/

 

Thanks! I checked the AC drain - that 90 degree metal elbow sticking out of the firewall, and it was free and clear. I actually took it completely out of the firewall and put it back in. Based on what I'm reading, should I also try to stick a metal wire into that hole that the drain hose comes out of? Could that be clogged?

I'll pull my wipers off tomorrow and check the cowl area to see if anythings wet up there, if it's not the AC drain sounds like it'll be coming from this area.

 

Try to carefully run a wire up in it. Depending on your location and humidity, you may be able to test the drain by running the defroster and letting it drain off some condensation.

It had to spray water in the cowl to recreate the leak on mine.

My only regret with the Flex Seal with not using the clear. The black gets very messy with clean up.

 

So what did you end up doing to fix? Use sealant along that pinch weld inside the cowl gutter? If so what kind did you use?

 

I used Flex Seal with a Fluid Film extension wand. I cut off the sprayer tip so the thicker Flex Seal would flow through it and used a coat hanger wire to make a wand for reaching into the corners. It took two treatments with 24 hours to dry between each before stopped the leak.

I failed miserably at trying to use a caulk gun with a plastic tube. It just would not flow through the tube like I needed.

I have a smaller leak that has returned at the center just over the transmission hump that started with freezing temperatures.

 

Here's a picture of the water leak before I applied the TSB fix using Flex Seal.

 

Thanks! Looks like it's coming from about the same place. Sounds like I have my next project cut out for me.

 

Where are you located? Warm weather is your friend.

 

I'm in Cincinnati. Unfortunately it's been raining like mad today and pretty much every day this upcoming week... but I'll find some time to get it done.

 

I had this same problem. I shot air up into the 90 to clear it. However I was talking with a co worker who runs our fleet at work said to use a vacuum instead of pushing debris in. I had no idea that defroster ran the ac unit causing my floor to flood. I just thought it was the rain. All n all my floor doesn’t flood and ac drain works.

 

@t_rex_94 - You are not alone my friend... I too am currently dealing with the same trouble.
Thx to all sharing their knowledge and experience - At least I've got the next five days off and no forecast of rain...

 

What's your plan of attack? I'm gonna go with liquid flex seal along that seam in the cowl gutter and hope that does the trick because I think that's where it is coming in.. My ac lines were fine.

 

I have my interior completely gutted right now because of this same issue. Gave me a good excuse to shampoo the carpet though haha. My ac drain was clear and ran the hose over the cowl for a good 5 minutes and nothing is leaking so I'm a bit stumped myself.

 

Pray it's not a rusted area at the bottom of the windshield.

 

I feel everybody's pain on this one. I can't comprehend working on this during cold weather outside.

The good news about Flex seal is it is more like a liquid and runs into cracks and crevices. The bad news it since it is more like a liquid, it took two coats. I let the first coat dry for 24 hours before applying the second coat. I had to keep the cab covered with a tarp between coats since it was raining every afternoon when I worked on it.

 

I think I'm gonna have to borrow a garage to tackle this one... no way am I doing this in freezing cold weather lol.

 

Highly recommended.

 

It rained yesterday and the passenger floor board stayed dry.

I think the last water leak episode, that appeared closer to the transmission hump, was from a recently clogged evaporator drain line. So there are two sources for the passenger side water leak. When the weather warms, I need to clean out the evaporator. I suspect some type of debris is flaking off and clogging drain line.