This might be long....but damn is it weird and annoying.
On the weekend I had noticed water *under* the rubber mat on the front passenger side of the 96 Firebird....Being a GM guy I am no stranger to these kind of leaks so I pulled up the trim, carpeting and underdash to start the process. Spraying with the hose I had noticed some water getting in through a grommet in the firewall where I'd run my power wire for my amp - sweet, easy fix, or so I thought. I siliconed the grommet, re-tested with the hose and called it a done deal.
Experience tells me though that these things are never that easy, so I left the carpet and everything pulled back so I could monitor...Car sat in the driveway in the downpours on Monday and guess what, I found another puddle in the floor last night. I dried it up and strategically placed paper all around the wet area in hopes of tracking down where the water was running in from.
Today I get home, car is sitting in the driveway and it's raining pretty good again. I get in the other side and guess what - there's a puddle, but the paper perimeter around the puddle is dry! I know it's not coming from above either because the rubber mat was always dry. I get my flashlight and stick my head down there to have a really good look. After I few minutes I see that the water is actually dripping from the wiring harness...but after carefully investigating, the water is coming from the INSIDE of the harness. Basically, this piece of harness consists of about a dozen wires all wrapped up in electrical tape. They come from the pcm in the engine compartment, through a firewall grommet and then into the dash area...water from the wiper cowl drips off onto the wires in the engine bay, it penetrates a gap in the electrical tape and runs a good 2 feet inside the harness tape to the lowest point, which happens to be in the car, and then seeps back through the electrical tape and onto the floor.
Should be a reasonably easy fix on the weekend, but I've never seen anything like this before....Talk about obscure. I also cannot believe how many different interior water leaks I've dealt with in the last 5-ish years...the Sonoma alone has had at least 5 separate leaks, the 96 bird has had 3 (including this one) and my grandmother's 2000 Buick Century has had 2.......I guess I deserve this for buying so many old GMs of shoddy build quality, but this last leak is really getting ridiculous.