2007 Tacoma With a Cowl Cover Water Leak issue

Hi all,

I have had a 2007 Tacoma Sport for about 14 months now, it was a one owned with under 80K on it when I purchased it last year. I have had a series of problems with the truck, but this one I am having trouble figuring out. I see there are other discussions threads on this particular leak in the cowl cover just below the windshield, but after reading several I am having a hard time telling what people are saying needs to be fixed and or sealed.

So this leak is on the passenger side and is only after a good storm, the symptoms are just as the Toyota Technical bulletin describes it to be.

Water enters from the outside of the vehicle through the blower motor housing and the blower motor. This is just what is happening with my vehicle, after a storm the other day there was about 2" of water on my all weather mats dripping down from the blower motor. I opened up to look at the cabin filter and it was saturated. No other water entered the truck aside from this spot not even on the carpet.

So my question is...after removing the wiper blades and the plastic cover shield below, you get a clear shot of the entrance to the motor housing (see picture 1), this is where I am assuming the water is entering. All drains on both the left and the right are clear. I can see how easily it would be for water to get into the housing but I cant see HOW the water is getting into the housing.

Reading over the service bulletin, it mentions using automotive sealer in the left and right corner, but I don't see a crack or separation on either corner. I was wondering how others solved this problem? I was thinking possibly a shield of some kind over top of the open vent below the windshield but it seems the plastic cover that hides the open vent has a kind of built in mini shield to it on both the left and right side already (see picture 2)

Can anyone who has had or solved this problem tell me what needs to be sealed ? Of course I asked the dealership today and they told me to contact a windshield company. But this doesn't have anything to do with the windshield it seems more like a design flaw.

Thanks,
Rob

 

Are you absolutely sure the drains are clear?

 

Well I took a 5 gallon bucket of soapy water and poured it in the center and the water flowed both ways freely...the drains I am talking about are on both the left and right side. I guess its possible one is clogged but they never slowed down, filled up or became clogged when I was pouring the water. Is there a way to clean out the drain? I can put my finger into it and there does seem to be a little bit of crud in there.

 

I dunno. Maybe torrential rain will overflow the thing. Perhaps a larger diameter tube revision is in order.

 

You know Steve, you might be right the drain closer to the front of the car looks open but when I stick my finger inside I can feel something in there. Maybe I will go that route first (cleaning the drain) there doesn't seem to be any access to cleaning that section out as it seems to be behind the fender. I know the one closer to the windshield has access from the door jam when you remove that cover.

 

I just picked up a 2007 4X4 with 8600 miles and it's leaking too. I assume from the same area. I stopped by the dealer & the Dude said there were no service bulletins about it. I need to fix this issue. looks like it would be easy to build a cover for that air box. I'll check it out tomorrow. Dang it.

 

Mine is 2007 with 116K and I'm having the same problem after the rain a few days ago. Any updated fix for this?

 

Yea the fix is simple, mine was a clogged drain line. It was kind of hard to see but using high pressure water will blow all of the blackage out of the drain line. I was sure that it was not a clogged drain but after removing the cowl cover and letting the water flow down the windshield the level under the cowl would continue to rise until it overflowed. Once the blockage was removed haven't had the problem again since.

 

I'll check it out and see if that's the case with my truck. Thanks for the info!

 

I had this exact issue and was going bonkers because my car had been hit in the right front and I thought the leak was crash-related. Was not the case. Whenever it rained, my passenger-side carpet got soaked and started to stink in a few days.

You have to build a mini-roof that goes over that inlet. I ordered 1' x 2' galvanized steel (28 gauge) from Amazon and cut a pattern using cardboard as a template. Use sealant against the firewall and affix somehow. I used zip ties on the two holes on the duct. Here is an example that is a little rough but functional: https://www.tacomaworld.com/threads/water-thru-cabin-air-intake-my-solution.88655/.

 

It's great advice but it's a 7 year old post. But thanks anyway my 07 hasn't leaked yet by now I'll now what to do

 

Yep. My '07 didn't leak either until I moved to where it rained.

 

So this happens most of the time when the front windshield is replaced ! Or after owning truck for long period of time. Cause for leak is “The Cowl” when they remove this piece they break the clips that hold it in place. Unfortunately it’s a costly fix. Have to replace the whole cowl. When removing the cowl you have to squeeze the clips in and then push up, from engine compartment . Water usual comes in through cabin air intake. Because cowl is damaged and no longer secures tightly to the frame. I’ve had this problem before. It’s every time they replace the front windshield. They rip up the cowl. Which breaks the retaining clips. Cheap way to fix it is to cover the air intake under the cowl. I do not recommend this though. Sorry for the lengthy answer.

 

well.... this is happening to me, I just had the windshield replaced a few weeks ago. i can see clearly that the water went in via the vent

 

Do the roof thing. Mine hasn't had an issue since.

 

roof thing??

 

See above:
You have to build a mini-roof that goes over that inlet. I ordered 1' x 2' galvanized steel (28 gauge) from Amazon and cut a pattern using cardboard as a template. Use sealant against the firewall and affix somehow. I used zip ties on the two holes on the duct. Here is an example that is a little rough but functional: https://www.tacomaworld.com/threads/water-thru-cabin-air-intake-my-solution.88655/.

 

Thanks for the info. I have some flashing material but all my tools are at a job site. I think I'll be able to tackle it this weekend. I Can't believe how poorly designed this is, What were Toyota engineers thinking? also looking at the 2 holes I think something was deleted to save money. Also I noticed that one of the small tabs in the cowl is missing and the top seal doesn't sit against the windshield. Maybe because it's an aftermarket windshield.

 

Agree. However, this and a bad u-joint are the only issues I have had on my 2007.

 

1. PELE sells a 3d printed cowl shield
2. The stock plastic cowl has a TSB and about 4 part number revisions advising the old ones have a leaky gap and to replace it.