Ok, so I was coming home yesterday and noticed that the car in front of me slows down some and moves towards the middle of the road. Thinking he was turning, I maintain speed. WRONG! HUGE amoune of water covering the road, about 8-10 inches (yes, Rochester and water suck) so I hit it doing ~35, which after a second turned into ~15. So anyways, I get out of it and all seems well. Hit the gas and I hear a really loud sound like air is passing by something and it seems like it is coming from the exhast area under the front floor.

Happens at 1600-2000 RPM only, can't hear it all the time. The only sound I can liken it to is a PT Cruiser with a rice pipe (brother had one) I checked the intake and it seems fine. crawled under it and didn't hear/see anything out of place.

Does anyone know where this would be coming from? is it possible to only hear it at certain RPMs due to resonance frequencies? I am thinking I moved/stretched/broke/loosened something with the exhaust on the car. The car runs fine otherwise.

also noticed some rust and a dent in my gas tank too.

you gota clutch fan on it???????

I've never seen a FWD with a clutch fan, especially a 1998.

I know that!!!!!!!!!!

sounds like he'* in a truck, ........with the Rochester

Sorry... the LTZ is the Lumina, Rochester is the City I live in. Apparently it doesn't like to drain after hard rains.

Crawled under the car today. Could not notice anything under there that seemed amiss except for some surface rust, a dent and a dented gas tank (was there when we reinstalled it.)

think it might be vacuum related, like a hose giving way under load?

ur lucky, U didnt have to drive in that heavy storm, I did on my way back from there, and lemme tell you this, it was at full force when i hit it in the middle of ohio, hydroplaned 3 times.....ugh. add bad wiper blades into that equation and you see how much "fun" that storm was :P

Well just keep an eye on it see if it keeps doing it,
Somethings take a wile to pinpoint them down, You'll get her