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Discussion Starter #1
Opened the car door this am and was nearly knocked over by the smell of wet/mold/bleh. Turns out the front pass floor is soaked. 100% sure its water, too. Not slippery and no coolant smell. Carpet was drenched around the footwell near where the AC drains out through the firewall, but the foam around that nipple was (and is) dry. 90-degree elbow was there in the engine compartment. Nothing blocking it. Padding under carpet is soaked on the passenger side, as is the pad in the footwell. Pulled it all out to dry. Was wettest around the center, center-right of the firewall pad - the rubber stuff - and the footbox itself, which lends validity to the drain being the culprit. Pulled the drain pan off (PITA) and it looks ok. No cracks and the hole was clear to drain. Looks like someone was in there at one point and used silicone sealant along the edge to seal it up.

I know everything is pointing to the condensate drain being the source of my water, but there was nothing blocking it - so I am stumped.

Pulled the cowl covers and cleaned out the cowl. Dumped a bunch of water in there and watched for leaks - nada. Dumped water on the windshield - no leaks. Inspected the firewall and floorpans in the engine compartment and under the car - no rust or holes. Its tight as a drum under there.

Any ideas ladies and gents? I am going to seal it all back up and pop it in - hoping for the best, but it doesn't make me sleep any better not finding any obvious cause of the water.
 

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It appears you're dealing with a wagon, so I'm sure you've traded notes on usual leakers with fellow longroofers. Sedans have their own collection of places that corrode and fill up the footwells. Good at least to hear it's limited to one side. Also, sure you heard the trouble running heavy A/C (especially at speed) if the drain elbow and downtube is missing and condensate wicking back inside. Your description sounds like more than just a single day in high heat though. If it rained real hard, - and you were parked downhill, - and the rear roof-to-door leaks, or fenderwell rotted out, then water can run from rear to front. I had a ghost leak in an '80 Riviera turned out to be a long section of urethane broke loose from the bottom of the windshield. A spray hose never showed it. But I noticed the windshield moved one day when closing the door! Had it reinstalled and no more leak.
 

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Check the antenna grommet. It is behind the wheelhouse on the passenger's side. It is just below the cowl drain. I also had a window unseal along the bottom edge It was a real PITA.


I painted a 1/2 inch line on the floor around the edge of the footwell, with water soluble paint. If any water gets in, it will wash the paint away in that area.
 

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Since you have the carpet out, have someone run a hose around the exterior of the car while you're inside checking for any trails of water. Have them start low and work their way up, paying particular attention to the area around the cowl, window seals, and roof rack. If no leaks, then it's likely your AC tray.
 

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Discussion Starter #6
Thanks for the suggestions. I've investigated them all - including having a hose moved around the car while I watch for leaks inside. No dice. Here's hoping it was the AC pan.
 

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Another way to check for leaks is to put a shop vac in the cargo bay, and run the suction hose and cord out of the vent window. Seal the intake for the AC (under the cowl), window, hose, and cord. Put the windows up, turn the vacuum on, and put kid's bubble liquid, or slightly diluted dish washing liquid on any place/area that might leak. Bubbles should lead you to the source.


There are two sizes of drip pans, so if yours is cracked, make sure you get the right one. I found one on a buick that was longer (front to back) than the one in my OCC.
 

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Most likely is the AC Drain line is plugged causing it to go into the interior. Hard to diagnose easily. but if you turn on your AC and it doesn't drip outside...

Can also be rust around the windshield causing it to leak... Requires removing windshield, repairing rust and reinstalling windshield.

Sunroof? It has drains that can become clogged or disconnected causing interior "flooding".

Those are the main culprits I am aware of.

Rodney
 

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Should the sunroof leak, it will drain down the B or C pillar. There is little chance that it will end up on the floor, especially the front.
 

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Yo Fred,
I recently went through my 'Astroroof' for several issues. To re-upholster the lid, try to reduce wind noise, attend to leaking on the pass. seat through the carwarsh... While in there I ran a fishtape down all the tubes and I recall them being the A and (either B or C pillars), but unimportant which as they're easy to scope out and clear with the headliner down. All my drains were clean, but if Mr. -dan has one it would be worth checking as it can certainly leak down forward of the backseat if so inclined.

My 'leaking' (and the wind noise) was/is simply the gasket (thin felt U-band glued to the glass frame) wearing down enough over the years that it'll never give good seal. With a hose I can see water going in, but not normally any leaks. The carwash is just too much for the the tubes to carry away hence the overflow over the capture channels.
 

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Discussion Starter #11
In the process of troubleshooting, I removed the lid and re-sealed it with Permatex black. I removed my cowl covers and removed any and all debris (there wasn't much) so I could inspect the cowl. I ran a bore-scope down in the tight spots - no rust. Removing the cowl covers made inspecting the lower edge of the windshield seal for rust quite easy - nothing to be seen. Same with the sides of the windshield - no rust. Stuck a hose in the cowl and ran it for a while - no water in the car. Jacked the car up and inspected the firewall and undercarriage. No rust or holes, so there's no way I can see for water to get in via being splashed up. Also checked Fred's suggestion of the antenna grommet - its good.

Ran a hose along the roof rails for a while to see if the outer rack-rails were leaking. No water. Ran the hose along the roof to where it cascaded down the windshield for a while. No water. Ran the hose along the outer door-seal. No water.

While drying out the floorpan, I noted that it must have been getting wet for a while. The clip that holds down the wire trough on the outer-edge of the pan was completely rotted away. There were also some rust spots underneath the carpet. They were all wire-brushed down to good metal, then treated with Ospho, then painted over.

Have not driven in the rain since the work was done, but have had the ac running. No water. Waiting to re-install the doorjamb plastics until we get a good rain so I can easily inspect the pan.

Thanks for the suggestions

P.s. - taking the cowl covers off is a great time to clean them, wipe them down with acetone, and give them a shot of satin-finish black. They look brand-new. Sand the wiper arms down, wipe them with acetone, and paint them with satin black. They also look new.
 

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The vista glass on the 91-93 cars was installed with urethane. The 94-96 cars were installed with butyl. The 94-96 vista windows are a lot easier to R&R. They rely more on the studs and nuts to hold them on. If you need to reseal them, it is really messy, but not to difficult. The butyl will come off fairly easily, and then it is a matter of putting new butyl in the channel, and reassembling the unit.
 
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