Okay you guys are gonna like this one. I found the leaks on the '97 crown vic. Recap: first found water under passenger foot well behind driver. That was because it was easiest to check. Finally got tired of messin around and pulled out all the seats and carpet. Turned out the entire drivers side front to back seat was soaked. Dried it all out and watched for water entry. Was coming from the front and somehow making it over the ridge to the back. When I parked at an angle on a steep driveway I saw it pond in driver's footwell and run to the back, so I figured that ruled out door gaskets. Pulled the accelerator pedal supports and lower dashboard plastic covers. Insulation under firewall shroud was soaked. On outside pulled the windhshield wipers, screen, and the big plastic wiper well with wiper transmission. Let a hose drizzle along different spots. Found two leaks and watched them coming in. One was the rubber boot where the hood release goes through the firewall. The cable runs upwards so any water hitting it runs down and goes through the cracks in the boot due to aging. Resealed with RTV. Slowed, but still leaks a little so will really gob the stuff on and may figure some other kind of seal for it. Next, the real big leak was coming in at the accelerator cable through the firewall bracket. I watched the natural flow of water off the windshield and it just dropped right on top of it. The seal eventually failed. I pulled the bracket and cable and resealed it with RTV and reattached all. Let it cure 24 hours and put the hose right on top of it, plus we have had several days of rain and it is dry. Plus I can't see anything coming through when I use mirrors to look up under the firewall shroud.
Told my wife we're leaving the carpet out until I know it is remains dry and problem is solved. Which means all summer through early fall (that's when the rains really start in Washington State)! Got the smell out of the carpet padding by washing in my backyard with carpet cleaning solution, rinsing with the garden hose, soaking with a weak bleach solution, rinsing and then letting dry in the sun for a few days on my back deck. Not sure if that was worth it as padding is pretty cheap at auto body supply stores, but I was on a mission!
My advice for others is to go through the effort to yank the seats and carpet, dry the floor and then observe. There is a lot of stuff coming through the front firewall and any is likely to leak under the right conditions. The problem in identifying it is the black firewall interior shroud and insulation under it doesn't remove so you have to try to pull it up and try to see where water is entering. You have to be a bit of a contorsionist and use flashlights and mirrors!
Right now I'm feeling pretty darn good...we'll see how long that lasts when the rains come! Hope this helps you guys....good luck!!:driver: