After rain, I am finding major wetness under and behind the driver’s seat. The roof drains near sunroof have been cleaned out and there is no visible sign of how water is getting in. Help!
Other typical culprits are leaky windshield and also backed up or misguided A/C condensate drain tube.
My 2000 Blazer had the same problem. It had been in a fender bender before I bought it in 2003. There was a split in the seam between the firewall and the inner fender.
I found the leak while shining a flashlight under the dash while running water into the cowl vent in front of the windshield. The water was running down the seam under the carpet padding and collecting under and behind the driver’s seat. Also check the bottom of the car for missing drain plugs and openings. Once the leak was found and resealed there were no further problems.
Ed B.