The truck is leaking water into the driver's footwell...

[ShooterMcGavin]

I have so many problems with this vehicle and now I have a huge roadblock to fixing it. I don't have my garage any more, with all my tools to fix it. I am staying at a friend's house, with a garage, and soon my truck will need to be parked outside in about 2 weeks. Most of my tools are in storage, but I have the small set of tools that I always carry out into the woods. I need to find this leak and get it fixed!!! After it rains, the whole driver's footwell and carpet becomes soaked. I have looked up in the footwell and I can see dampness on the firewall. My windshield has a large horizontal crack starting from the left pillar. I don't know if that would cause this leak though?

What are the most likely culprit areas I need to inspect? I need to get this done efficiently and quickly because I don't have much time and limited tools. Do I need to take out the entire dash and console to get down to the bare firewall for this?

 

[97FR_brad]

Maybe the leak might be coming from the wiring grommet coming through the firewall. I had the same problem after fog light switches were installed. The grommet let water through at that location.

 

[kolelt]

How is your grommet that the OEM wires go through ? Do you have extra custom wiring going through ?

Spray some water on there and quickly look inside the truck. See if you can see water. Or have someone do it for you. Make sure to peel the carpet so you can visually see it.

How is your gasket around the windshield ?

 

[diverscale]

Since it seems that you get water when the truck -sits- in the rain:

Look at your headliner if it has traces of moisture. Even if it does not have any, look at the roof black outer trim's bolts, take them off and put silicon on all the bolts.

a crack in the windshield, as far as I have experienced, should not cause a leak. You could try to look under the trims if you could see an opened rust spot, which could cause your problem. If for any reason you could see that the crack is causing the leak which I doubt, there is a windshield high-flow silicone available https://www.permatex.com/products/adhesives-sealants/permatex-flowable-silicone-windshield-glass-sealer/

Look at all the door's rubber weatherstrips for any sing of leaking by inspecting the rubbers, or use a hose if you can.

I personally bet on the door weatherstrips or the outside trim bolts.

 

[cblock406]

I went through this on mine a couple years ago. I started by making sure my sunroof drains were clear, I had a new windshield put in with new seals, I siliconed the pass through in the firewall were I ran some wiring through to the cabin, and I siliconed the rubber floor plugs under the carpet.

This was all during winter in the Seattle area so it never dried out enough for me to pinpoint what fixed it, but two years later and mine is dry as a bone. Good luck, it was super frustrating for me too!

 

[Kotrin]

After you check all the seals what are the other problems you are experiencing? Also where in the PNW are you located? I'm in Oregon and if you needed some assistance I could try to see what i'm able to help with.

If its only wet after a heavy rain certainly sounds like a seal around the window. I didn't see you listing out a sunroof, but I just dealt with this last month. It was fine last year but it gathered some gunk over the year and I had to clear it out. Works great now

 

[Unner]

I bet it's that grommet on the firewall. Seal it up with some RTV and you should be good to go. No need for tools for this one.

 

[ShooterMcGavin]

Thanks for all the assistance! That grommet is sounding like a common source of leaking issues. I will look at it.

The gasket around the windshield looks fine on the driver's side, where it's leaking. On the passenger side, it looks worse. There are some small rust bubbles at the window seal, which I could see causing a leak. There is no water coming into the passenger footwell.

I've looked closely at the headliner and it seems completely dry. I was actually hoping that I would find wetness there, because that would be an easier problem to access. It could be the door weather strips - they are in bad condition, however the moisture on the inner firewall leads me to think that isn't it.

I am up north of Seattle now. Thanks for the offer Kotrin. The 4Runner was sitting outdoors for almost the last year, so I won't fully rule out the sunroof yet, but I will look into that grommet first.

OTHER issues I am fighting, and living with... No 4wd. It broke almost 2 years ago and I haven't done the inspection to fix it yet. Rear diff locker is broken. The details are in my build thread. More regular popping out of first gear, unless I hold it into first as I let the clutch out (I have a poly shift seat bushing). Just started hearing a loud clunk in the front. It is my front anti-roll bar again. I am using aftermarket poly bushings and the bracket on the passenger side pulled free from one end, bending the bracket completely. Interior lights not working is wearing on me. Broken drive shaft zerk needs to be drilled out and re-tapped. Torn CV boot on the driver side. Rear axle seals are leaking and rear brakes are worthless - no parking brake either. Transfer case seal is leaking, causing a drip on my friend's garage floor and she's not cool with it. All of this work, I can do myself, when I have a garage to work in and my tools.

 

[ShooterMcGavin]

Here is a photo of one grommet with alarm wires going through the firewall. Could this be the source of the leaking? How would I seal that up? I guess I could just stuff some silicon caulking in there, but is that the best way?

*ETA: I guess photobucket won't allow photo posting any more?

Here's the link to the photo, if anyone is curious:
Firewall grommet and wires

 

[97FR_brad]

Here is a photo of one grommet with alarm wires going through the firewall. Could this be the source of the leaking? How would I seal that up? I guess I could just stuff some silicon caulking in there, but is that the best way?

*ETA: I guess photobucket won't allow photo posting any more?

Here's the link to the photo, if anyone is curious:
Firewall grommet and wires

Silicon seems to be working for my truck. I used some rubber gloves and dabbed some on the fingers and filled the crack. HeHe

 

[MarkamisPrime]

Check your sunroof
The RF drain runs down the kick panel and through the floor board
There are also drain plugs on your floor board maybe one fell out
I doubt it’s your firewall
Not too much water actually runs down it especially if your driving

 

[gamefreakgc]

Link doesn't work either.

And GEEZ photobucket is swarming with ads.

 

[ShooterMcGavin]

Check your sunroof
The RF drain runs down the kick panel and through the floor board
There are also drain plugs on your floor board maybe one fell out
I doubt it’s your firewall
Not too much water actually runs down it especially if your driving

I can take a look again. It seems to leak water when the truck sits for a while in the rain. I don't know if it is leaking while I drive. After a rain, I have checked the headliner and it seems to be dry. Would that rule out the sunroof as a leaking point?

It does seem odd that I get that much water inside the truck for such a small hole in the firewall. Not sure.

 

[ShooterMcGavin]

Link doesn't work either.

And GEEZ photobucket is swarming with ads.

Sorry about that. Yeah, I am getting tired of all the ads on photobucket. I log onto the site and my computer freezes up for 5-10 seconds as ads try to load and display. No other site that I visit does that.

 

[Scramble]

99.9% of the time its the sunroof drains. They either get clogged or the drain tube shrinks with age & falls inside the cabin instead of draining outside.

I'm glad my T4R doesnt have one but my last three cars have.

hey! It's 2017, no one uses Photobucket anymore.

 

[CB3G_GM]

I just spent some time tracking a leak on my passenger side. Turned out to be the two AC line grommets were loose (used rubber sealmaker to rejuvenate the grommets) and the line of factory sealant at the firewall/cowl junction had degraded and started allowing water in under heavy rainfall. The channel under the cowl drains out along each side of the fenders.

If you can get access to a hose I would recommend checking each area one at a time starting from the lower spots and move upward. For whatever reason when there is a really hard rain the cowl area gets overwhelmed and it drains down along the firewall. I would try simulating rain at the suspect grommet(s), then run water over the cowl area, then start working your way up the windshield checking for leaks after each step.

I ended up having to pull my dash to get to mine. Hopefully yours will be easier to find/fix.

 

[ShooterMcGavin]

99.9% of the time its the sunroof drains. They either get clogged or the drain tube shrinks with age & falls inside the cabin instead of draining outside.

I'm glad my T4R doesnt have one but my last three cars have.

hey! It's 2017, no one uses Photobucket anymore.

What are people using for photo hosting now?

If it is clogged sunroof drains, won't the water seep in and soak the headliner?

 

[wcjeep]

With a different vehicle I removed the seats and carpet. Then had the wife use low pressure water hose on the outside. Didn't take long to find the leak. On that vehicle it was the front windshield gasket. I ended up using windshield gasket rtv type sealant under the gasket along the driver side of the windshield. Also steam cleaned the carpet while removed from the truck.

 

[Kmurt]

Ran into the same problem after I ran a cable through the firewall. Drivers floor mat soaked after a good rain. If you ran any aftermarket cables through the firewall, this may be your problem. I sealed mine up with a lot of black RTV and it has been dry ever since.

Here's a video I took trying to find the problem after spraying water on the roof, hood and windshield. Click the picture for video.

20160825_103430

 

[Scramble]

What are people using for photo hosting now?

If it is clogged sunroof drains, won't the water seep in and soak the headliner?

Flicker is great & that's what most people here are using.

Not if it's running down the A piller.