GKK

I've been trying to figure out how the carpet padding is always getting soaked with water in my "91" Vette.

So far, I've replaced all the weather stripping around the windshield, targa top sides and rear hatch with GM weatherstripping. That stopped the water from entering from the top but, after removing the carpet from the passenger footwell, I noticed that the padding was soaked with water.

I removed the padding, washed and let it dry overnight and reinstalled. a few weeks later I checked it and found it damp again. It's not the heater core because it doesn't smell like coolant. I noticed there is a rubber foam backed piece of material laying up against the passenger side firewall that is soaked with water but, I can't figure out how it's getting wet. Everything above this point is dry.

This is the highest spot I've found it wet and it wicks around the sides of the transmission tunnel and stops in front of the seat track.

The top of the carpet, right front speaker panel, side rails and door panels are all dry after washing the Vette. Also, the floor pan is in perfect shape with no holes or cracks anywhere and all drain holes are draining fine.

After pouring a lot of water at the base of the windshield, and looking in the footwell area, I can't see any water dripping in. I've read that the A/C drain tube could be leaking condensation into this area but cannot find where this tube enters the firewall.

I'd appreciate any suggestions. Thanks

1quik91

HEATER COIL, Goood luck!

GrtWht91

This happend to my 1991 also, I ended up removing the seat and carpets to figure this out...finally after searching what i found was a little trap door under neath the carpet to the right side of the car and water was coming through there, so i had to figure out why, it came out the the cowl (the place between the windshield and hood) was clogged with trash and the only place for the water to go was in the trap door (the trap door is used for the A/C therefore the cowl brings in air for the A/C) so there are two drains on both sides of the cowl (one by the between the windshield wiper fluid canister, and one kinda behind the battery), driver and passenger, get someone to help and take a water hose and put water into the cowl, feel around and find those drains and use your fingers or an long object to clean them out, solved the problem for me...

Jet-Jock

A small pin hole leak in the heater core will cause the cabin to smell like coolant. I know I had one, it wasn't enough to even cause moisture in the heater core housing but enough to discolor the core. I've been in there recently and replaced my core. I am not aware of any condensation drain that would be inside the cabin. The evaporator attaches to the firewall just below the coolant surge tank. If you can jack up the right front you can see where the drain is and make sure its not plugged up. Some how leaves can get in there. I cleaned mine out last oil change. What may be happening is your collecting moisture in the housing and its leaking back through the firewall at its attach points near where the heater core lines feed through the firewall.

With the amount of liquid your describing you'd have a sticky mess it it were coolant.

Next if its a coupe remove the top and examine the weatherstriping along the top of the windshield. You can lift up on the forward edge, it should be seated into a channel piece. If you have any breaks there, it could also be water running down under the weatherstrip channel then into the sidewall where you described.

Hope that helps some.

GKK

Thanks for all the suggestions.

As I've mentioned before, all of the drain lines are clear including the A/C drain. Also, there is no water dripping from any trim panels or weatherstripping above. Everything is dry from the door sills up.

With the carpet and padding removed, and water poured from a hose, I don't see any water dripping in.

It looks like the water starts from the firewall area since behind the rubber padding is the wettest but, everything above this rubber padding is dry. Also, everything in front of the firewall is dry inside the engine compartment. It's not the heater core since it's clear water.

I'll keep checking things. Thanks everyone.

LSUgoTIGER

my 93 did the same thing, exactly as you describe for about 2 or 3 months....I had the drain plugs cleaned out....but it still continued to drip for a month or so.....and then one day just stopped.....and hasn't done it since.?....I'm not too interested in why it stopped, just happy that it did. I'm pretty sure it had something to do with the AC, because it would still be soaking wet after driving around on the most beautiful days, with the AC on...

Adam

HG

Water leaks and C4's are like bread and butter. So, here is my experience with leaks. Where the metal trim meets the windshield was leaking when the car was out in the rain. Ran a very small bead of silicone along the edge and it stopped. Probably not that simple, but a shot. Good luck.

GKK

I'm going to remove the carpet, padding and seat then, sit in the vette and have my son spray water until I see it leak. I hope this works.

Midnite 88

At the base of the windshield there are 2 areas that have a "screened" in area that the climate control uses to pull in fresh outside air. there are 2 drains in this area (one on each side) make sure that these areas are draining properly. If the drains are clogged the water will come in through the heater/ AC plenum and soak into your carpet.

Good luck to you and let us know what you find.

Mike.

dndrsn

Did you clear this drain under the plenum ? It's kinda hidden in behind the gill plate and the windshield washer fluid tank. Even if it's clogged it will drain some. I would make sure it is completely clear. Washing your car will fill the plenum up fast.

GKK

Yes, Both drains work fine.

I poured water into both screened areas and put my hand under both drain tubes and the water came out fast.

Captn

Hi GKK, You mention two drain holes, I have freed the one beside the W/W container, could you point me to where the other one is? Thanks, David...

HG

I think he is talking about the other sump under the drivers side windshield. There is a small black hose theat runs down in back of the battery that also gets clogged. You can reach in and pull out the hose to check the bottom. This one gets clogged easily dut to the way the bottom seals. I don't think this would leak on the passenger side, just the driver side.

GKK

HG is correct.

The other drain tube exits directly behind the battery.

CMYC4GO

Been there, done that. If it ever happens again, I'm just going to commit suicide, and leave the nightmare to somebody else!