Odd Noises

I have a 2005 Mazda 6i with 88,000 miles. I just replaced the rear brakes, gas valve cover, ignition wires, spark plugs and got an oil change. The guy didn’t know what the sound was that I was concerned about. This is the best assessment I have of the “odd noise”:

1. The sounds is coming from under the hood of my car.

2. The “sound” is similar to a portable fan on medium speed when you put a piece of thick paper or thinner plastic into the blades.

3. The sound occurs between 0-39 mph and ceases as my car changes gears and/or I am going over 40 mph…and not all of the time, but most of the time. It seems to stop randomly.

4. No other odd behavior is occurring with my card aside from this sound.



I am going on a trip this summer to the west coast so I’d like to figure this out/possibly fix it myself before I leave!



Thanks for your help/suggestions!