Buzzing in engine while driving

Hi all,
I have a 2000 Mazda Protoge. I recently had the air conditioning fixed and primarily afterwards (although it could have been quiet before), when I accelerate or perhaps when it is thinking about shifting gears, I hear a strange buzzing sound, like a fan is hitting a bit of metal or something. It isn’t too severe, but it sounds like it might be getting a little worse. Not louder, just more often. Any ideas? Belt? Two things touching? Should I bring my car, or is this just growing pains?

Bring it back and let them know. Chances are that it’ll be minor and they’ll fix it for free.
New noises should always be checked out. There are no such things as growing pains.

My 2000 Blazer had the same sort of noise after the intake manifold gasket was replaced. The accelerator cable was the source of the noise, it was not properly secured in the engine compartment . One tie wrap later the noise was gone.

Ed B.

Or maybe your fan wasn’t properly secured. Who knows. One thing for sure – the noise won’t go away, it’ll only get worse. As mountainbike sez, have it checked out.