Drove through water, now there is a strange sound.

I drove through a large puddle of water three nights ago when it was raining. The water went up over the hood, I accelerated to get out of the water and got out fine, but yesterday and today I have noticed a strange noise coming from under the hood on the passenger side, down by a belt. You can hear it when you start the car and when you are accelerating. The car does not feel any different while driving, and there are no lights that came on. It sounds kind of like a metallic sound. Like a whiny, whistle sound. I went and washed my engine and cleaned down by that area, the sound is still there, but not as loud. I have not checked any of my air filters or even my oil. All the shops around here want to charge $100.00 to just diagnose it and that is not counting if they have to hook computers up. Any idea of what it could be?