I have a rust hole on the firewall about the size of a quarter right where the firewall meets the driver's inner fender, just to the right of C100. Every time it rains, water comes through on the driver's floorboard. It's been raining every day in Georgia for the past 4 months straight, and I've had this problem since I bought the car 5 years ago, so this is getting really old. It's much worse when driving in the rain, as the wipers push all the water off the windshield into this location. I pulled a bunch of debris out of the bottom of the fenders years ago to make sure they drain properly, which they do.

Have tried 3M Seam Sealer, 3M Strip Caulk, Flex Seal, filling it with Great Stuff then going back over it with seam sealer, nothing works. The leak slows down for a little bit, then just opens right back up. Welding is now out too, thanks to my co-worker's recommendation of filling it with Great Stuff. This is the only rust on the entire car, but it's annoying me to the point where I'm considering getting rid of the car because of it. Have had the interior torn apart for almost a year now, constantly trying to fix it.

Does anyone have any recommendations for a fix for this? Only other thing I can think of at this point is digging all the seam sealer back out again, trying to cover the hole with JB Weld Steel Stick, then going back over it with seam sealer again.

 

Cut and weld is the best thing. If you cant cut and weld attach a plate over the hole using this stuff

 

The hole is now filled with Great Stuff, which is extremely flammable, so welding is not an option at this point. Will definitely look into this panel bond stuff though, if I can't come up with a cheaper solution. Didn't think an epoxy could cost $52 though! But still much better than selling the car, if it works.

 

I like POR15 epoxy putty... I used it to repair a rust hole on a car that also had water leaking in... But it was going under the carpet and never drying!

I used their paint also before adding the epoxy... They have some repair kits that provide everything you need... Never have had a problem.

 

As luck would have it, my work actually has 3M Panel Bond, and the $80 tool that you need to apply it, so I'll be trying that first, then POR15 epoxy putty if that doesn't work.

Thanks for everyone's assistance with this!

 

so how did it work out? any pics? dealing with same thing on passengers side