1986 vette.

So I gutted the interior of the car and redid the entire interior (dynamat, jute, carpet, and all). The thing i forgot to address before I put everything in was that water is getting into the passenger seat floor pan down where the firewall meets the floorpan. It seems to be coming from above and i am assuming its coming from the vents on the outside of the car in front of the windshield. The ones that are covered by a metal mesh cover. obviously I am not going to put water down there to try to figure it out because it will get down to my new interior stuff.

Has anyone else had this problem and know how to address it?

 

make sure it is not from the heater core...............


just sayin'

 

I got the leak right after i washed it down with a lot of water. Car wasnt even running. So i am just assuming it was a leak

 

Is it something like this
http://forums.corvetteforum.com/c4-t...nder-dash.html

(and no, I dont have the answer, this happened in a bad storm that there was so much rain I had to stop. Never happened again)

 

Very similar to what I had...It is definitely coming from behind the dash.

 

Also check that your A/C drain hose is not pinched

 

This is a tough one but not impossible to fix. I'd first check that the drain tubes in the cowl area are not clogged. There are 2 more or less on the drivers side that empty onto the engine bay firewall. 2 more are on the inside of the car, one on each side, down by the driver and passenger feet if you take the side kick panel off. And the 5th one is the AC drain tube that can be checked if you take the passenger side body work piece off. The piece that allows you to get to the blower motor.
Those are the easiest things to check so start there, but it could be that the large hood gasket seal is leaking. This is the piece that runs all the way from one side of the car to the other up at the cowl area and when you close the hood it seals against it. What happens is the sealant that seals it to the firewall breaks down and gallons of water race down the windshield and pour down the firewall and then through one of the many electrical connectors or body seams.
It's also possible that the weatherstrip on your door windows is going bad. Water will whip right around the glass, into the interior pillar piece and go right down to the floor like on a slide.

 

Well I fought this issue (still am to some degree) and have scoured the net for answers. First off, are you sure its comming from up under the dash (sounds like it). The big problem with these cars is the windshiled is glued in and the trim around it is also attached like that. The glue dries, gets hard, or cracks (body flex anybody?) once this happens the water enters all along the edge of the windshield. It then runs down the grove and enters wherever it can. I fixed 95% of mine by useing a tube of black silicone for auto uses (gaskets and such) i cut the tip very small and you can stick it under the windsheild trim. I then went down both sides of the windshield and filled the gap. 95% of my leaks are gone. it was originaly leaking in and running down the backside of the plastic piller pieces and onto the dash (and then behind it on floor). This method fixed my leaks around windshield, now i just get it in where the door meets the weatherstrip. it will drip on my rocker panel and run onto the carpet (where the door hits the rocker panel) and it destoryed my door carpet (well PO did). I need the 2 $65 peices of weather strip (about 6 insh long) that are on the top by the cowl... Ithink with them I will have 100% solved my leaks.. of course presure alwasy seeps in by the windows on side. no fix for that except udjusting windows in.. and that just cuases a bucnh more problems.