Water Leaking Into Interior

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PPV4ME
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Water Leaking Into Interior

Post by PPV4ME »

Hey guys,

For pertinent background information, my Caprice has 5 holes in the roof and 1 in the rear quarter panel that are all capped with hole plugs. My driver's seatbelt, driver's carpet and passenger rear carpet are getting wet...very wet. I have the console out right now and tonight I noticed a small stream of water running on top of my transmission tunnel, coming from underneath the heater/ac control area running towards the back. The wet carpet doesn't seem to be directly related to rain (atleast not always) so I'm thinking I may have a clogged or broken AC drain?

I'll try to organize my questions.
1. Does anyone know where the AC drain is on these cars and are they problematic at all?
2. The plugs in the roof are snug but they are not siliconed, could that be causing a large leak?
3. Any other ideas?

Thanks in advance for any help or information!

-Collin
CrashTestDummy
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Re: Water Leaking Into Interior

Post by CrashTestDummy »

Silicone on the plugs is probably almost a requirement, especially for the plug for the light bar harness, if your car had one. I opted to replace most of those plastic plugs with old, inop stubby antennas. I figured that the metal basses and o-ring gaskets would be better than some cheesy plastic plug someone jammed in the hole as fast as possible to get the car 'un-upfitted' as fast as possible. So far, I have been correct on two vehicles.
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JustDreamin
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Re: Water Leaking Into Interior

Post by JustDreamin »

I have heard that there was a problem with the AC drain and that there was a campaign executed by the importing agents (when the cars were brand new just off the boat) that was supposed to correct the problem. Not 100% sure on the accuracy of that report, but I believe it. Whether that is your current problem or not, I cannot say.

JustDreamin
Pursuit
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Re: Water Leaking Into Interior

Post by Pursuit »

I have noticed that the AC condensate drains onto my transmission and drips down the side of the transmission. Luckily it drains to the outside of the interior.

Maurice
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PPV4ME
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Re: Water Leaking Into Interior

Post by PPV4ME »

Well I think I have elminted the roof plugs as a suspect. The headliner has never been wet and water has still been getting in even when it's not raining. I am really suspecting the AC drain but have searched and cannot find it. Appears that maybe it's behind the shield on the firewall. Will post back with any findings.

-Collin
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elc32955
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Re: Water Leaking Into Interior

Post by elc32955 »

And, for wet carpet also don't forget to check for any holes from mounts for old police equipment that may or may not have been plugged. When equipment is de-installed after the car is permanently deadlined, the trustees doing the removal work generally don't seal things back up :)
System Manager and your tour guide for the day. 2015 Caprice w/LFX, former NC DPS staff car. Partial hybrid G8/SS/Camaro SS interior mods, SS MyLink radio upgrade, 2016 Camaro V6 rims, GMPP Malibu chrome exhaust tips, otherwise bone stock for now.
CrashTestDummy
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Re: Water Leaking Into Interior

Post by CrashTestDummy »

ESPECIALLY if you suspect they had a laptop mount installed. Those usually have a triangular-shaped base that mounts to the floorboard to the right of the console using 3 bolts.
Gene Beaird,
Pearland, Texas
2012 Caprice 9C1
1992 B4C 1LE Camaro
2018 Tahoe PPV (her car)
1995 DGGM Impala SS
1985 Firebird - 310 LS1 C Prepared autocross car.
1980 Bluebird Wanderlodge
And some others
Do YOU have my SPID?
PPV4ME
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Joined: Fri Jul 10, 2015 1:05 am
Location: Des Moines, Iowa

Re: Water Leaking Into Interior

Post by PPV4ME »

So I found out this entire problem is being caused by a grommet that surrounds where the AC drain drops through the transmission tunnel. This has been a huge problem with Holden vehicles (for sure VE series and WM series) for years and G8 owners both in US and AUS were getting their carpet replaced under warranty because of it...a few owners when the car was less than a year old. The inside of my car smells absolutely vile so I will be pulling the carpet and figuring out how to fix this properly, I will update as I find a solution. I encourage everyone to to either feel front driver's side carpet or if you have vinyl peel it back and feel the jute every so often because if that water sits in there for long, it starts to smell rotten and will eventually cause rust.

NOTE:To check or fix this you don't have to pull the carpet, if you remove the access panel on the left of the transmission tunnel (to the right of the steering column) you will see black plastic elbow coming out of the heater box going into a grommet...that is the drain.
9C1fanatic
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Re: Water Leaking Into Interior

Post by 9C1fanatic »

Thanks for the good info. Just curious, was your AC condensation still draining underneath the car in the area of the transmission in addition to flooding the interior of your car or was all of the water going in the car and none was draining below as it is supposed to.

Also would not be a bad idea to silicone those plugs in the roof anyway. If I remember correctly, the headliner has a plastic backing so if water was leaking in there it may not necessarily get the headliner wet as it did on older cars.
Garner Ames



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PPV4ME
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Location: Des Moines, Iowa

Re: Water Leaking Into Interior

Post by PPV4ME »

9C1fanatic wrote:Thanks for the good info. Just curious, was your AC condensation still draining underneath the car in the area of the transmission in addition to flooding the interior of your car or was all of the water going in the car and none was draining below as it is supposed to.

Also would not be a bad idea to silicone those plugs in the roof anyway. If I remember correctly, the headliner has a plastic backing so if water was leaking in there it may not necessarily get the headliner wet as it did on older cars.
I had no condensation under the car, but my wife was driving it at the time so I wasn't monitoring it as closely as I should have been. That was what finally tipped me off was that I never noticed a puddle under the car when my other vehicles were gushing water out.

Good tip on the plugs, my reasoning was always that if the headliner wasn't sagging or showing wet spots they must not be leaking. Wasn't even thinking about them having plastic backer boards now. I will do that!
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