your wife
Not much info there but my guess would be the the fuel pump.
Generally, this means your fan belt is old and wearing. I would recommend installing a new one, they are very cheap and easy to install.
A whistling noise indicates a vacuum leak.
It would help to specify the type of noise and type of vehicle in question.
If it's a type of clunking noise, check your gearbox. If it's some kind of rattling, check your hubcaps.
Loose belt - will sound like a screeching noise.
Could be your timing belt.
It is not normal for a timing belt to make any noise. It is whining because something is out of place. It is either under too much tension or there is not enough lubrication.
could be a wheel bearing...or just that its a french car
newdiv vacuum leak, cat. converter comming apart, exhaust noise
If the chirping noise speeds up as the truck speeds up, check the u-joints in the drive line.
The most common cause of the whistling in a 2003 Impala is a vacuum leak. Any of the lines under the hood could be causing the noise.