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Water draining into the front under the dash - not condenser drainage

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by gliderman, Jan 7, 2015.

  1. gliderman

    gliderman Active Member

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    Lets start off by totally eliminating anything that has to do with the condenser. It is NOT the problem.

    I have been having an ongoing problem with water leaking in from under the right and left dash and pouring initially then dripping. It is covering all the electronics and I am now afraid to go out in the rain. I am keeping my car covered and driving my truck in the rain. The problem seems to be worse on the right.

    I have taken the front trays off where the water drains to the side under the wiper cover and fresh air intake pan and there are no obstructions. I have sprayed water on the windshield and the air intake below, and it drains out the sides of the car. But when it rains, it seems to not go out the drains. I have cleaned out the drains and there is not any stoppage. It appears to be coming in through the firewall or the drain route has been compromised somehow. I dont know how it would happen on both sides with the drains clear.

    Anyone have a diagram of the water path on the 2010 Prius? Or a PDF on how to remove the fenders?

    Thanks!
     
  2. bisco

    bisco cookie crumbler

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    could it come in the roof seams and down through the pillars?
     
  3. gliderman

    gliderman Active Member

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    Thanks bisco! That was one of my thoughts. However I have poured water down the seams and it just runs out the normal drain channel. After I figure out how to remove the fenders and wheel well liners I will have a better idea of whats going on. But I dont have much time and any schematics or istructions would be very helpful and save me from making mistakes and removing something I didnt need to remove.
     
  4. css28

    css28 Senior Member

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    If this were a VW I'd suggest that it was leaking past the lower windshield seal but I haven't heard of this sort of thing on a Toyota.
     
  5. gliderman

    gliderman Active Member

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    I checked the seals on the window and it is in place correctly. But, it could still have a leak.

    Water is puddling somewhere because when I back out of the drive and step on the brakes is when I get a gush of water. Even though the tray under the air intake and wipers is dry. I checked.
     
  6. bisco

    bisco cookie crumbler

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    have you looked in the cabin filter area for signs of moisture?
     
  7. gliderman

    gliderman Active Member

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    No moisture in air filter, but the small try under it with the floor light gets plenty of water in it. I can see it pouring and dripping on the passenger side and on the drivers side it pours out the juncture between the left side cover and the door sill when I start driving.

    I'm going to buy a car cover tomorrow to help when it sits overnight in the rain we are expecting. I dont have time to take the car apart before next week.
     
  8. bisco

    bisco cookie crumbler

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    do you get a lot of rain?
     
  9. gliderman

    gliderman Active Member

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    No. In DFW area North Texas. We have been in a drought. Didnt notice it until a rain event in October. I think we have had four events since then. Expecting freezing rain and drizzle then rain this weekend into early next week.
     
  10. bisco

    bisco cookie crumbler

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    is it possible to hit it as hard with a hose as the rain does?
     
  11. gliderman

    gliderman Active Member

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    Yes, and I have. It all drains out the proper routes when I do it. But if it rains overnight, it is collecting somewhere. I havent found where. Or for prolonged periods it is soaking inside somehow from a diversion or whatever. But both sides at the same time? I dont know how that happens.

    It makes the window look more suspicious, but if it was leaking in the window, then I would think I would see it.
     
  12. jjngarcia

    jjngarcia Junior Member

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    Hi gliderman,

    Did you ever find out what the issue was causing the leak? I am having the exact same problem as you described with your Prius. I have a 2011 Prius III. I pulled up the carpet and found that the condenser drain is fine. The water comes in only when it's raining. About a year ago I got the windshield replaced because a rock hit it. I am wondering if the seal wasn't made well. I will attempt to take the front area of the car apart this weekend to see if I can find the problem. Any advice would be greatly appreciated.

    Thank you.

    Jesse
     
  13. edthefox5

    edthefox5 Senior Member

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    To the op using controlled spray hose fill up the front dam area the one below the windshield. Controlled meaning don't overflow the dam. Is the water poring out behind both front wheels?

    I think you have an obstruction there. Seen a few posts with same issue and its always an obstruction with the dam vents. Water should pour from behind both front wheels. How often have you see leaves built up in the air dam?

    Btw, if its pouring into the cabin its pouring onto the top of the engine. A misfire will soon ensue.
     
  14. edthefox5

    edthefox5 Senior Member

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    yes the bottom of the windshield was not sealed properly.
     
  15. gliderman

    gliderman Active Member

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    Yes. Sorry I never followed up.

    When my windshield was replaced, there was a strip on both sides where the adhesive never contacted the window. It was draining into the gap and down the inside of the front window posts. The strip on the drivers side was only two inches. The strip on the passenger side was eight inches. The installer showed me the gaps and said that there was not enough adhesive put on to evenly coat the glass and the mounting plate. And this was caused by the installer not pressing down the window all the way on the adhesive. I have since learned that it is a common problem that occurs but may take a year or two to manifest itself, as in my case.

    My windshield was guaranteed for life for workmanship from A1 Auto Glass. So a friend told me to call them and I did and when they came to fix it, I had a very long conversation with the installer about how displeased I was and I stood there and watched as he removed the leaking windshield and installed a new one. In fact he had another installer come help him so it would be sealed all the way around evenly. Both of them swore that it would never leak and so far it hasnt. They put adhesive on both the window and the window mounting plate. Normally they only put it on the plate. If they get too much it will slide and make a mess. With two installers they can do a much better job sealing the window.

    There is no more engine noise either which I noticed immediately.

    Even if you have to pay for the glass, get it replaced. But since you had it replaced already, check and see if it has a lifetime warranty on workmanship and call them. Didnt cost me anything and now I have peace of mind again.
     
  16. gliderman

    gliderman Active Member

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    The bottom of the windshield was sealed properly. And the way the plate sits at the bottom, it likely would not leak even if the adhesive was compromised.
     
  17. gliderman

    gliderman Active Member

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    After taking apart the fenders and liners and the tray it is easy to clean the drain. Simply blow air thru it or use a wire or coat hanger. You can touch the ground with it.

    That exercise was what made me believe that it had to be coming from above and sure enough it was, through the window posts.
     
  18. jjngarcia

    jjngarcia Junior Member

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    Thanks for the response gliderman. I feel better now that I can have a final solution. I spent hours this weekend trying to find the source of my leak. It wasn't the condenser drain or below the windshield where the AC intake is. I ran water there using a hose and it all drained down the wheel wells just fine. During my troubleshooting it started to rain so I parked outside and watched. Sure enough a slow trickle came in. I had the glove box and lower plastic housings removed along with the carpet pulled up. The source of the slow leak was well above the firewall. Water ran down some of the cables and then onto the carpet. I can't see exact entry point without removing the side moldings where the air bags are. The manual I downloaded shows that it's a difficult task so I skipped it. I'm almost positive it's from the windshield just like your problem was. The shop that did the windshield replacement agreed to reinstall it free of charge 2 days from now.
     
  19. gliderman

    gliderman Active Member

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    Great! It is such a relief finding a solution. I was worried sick about mine and wish I had the windshield replaced earlier.