High pitched whine while at idle
 

Could this be bad alternator bearings? :confused:

might be. check your fan belt tension- too loose or too tight?

Take a look inside your fan housing and see if there are any scrape marks. If the bearings are going, the fan may be wobbling.

Sam, is it a metallic sound or an "electronic" whine? Does it follow the engine RPMs?
If it's an electronic sound - when I replaced the 73E's CDI box & coil with MSD parts, I didn't get the coil wire pushed in tight and after a bit of driving, I heard a high pitched whine. After pushing it in firmly, the sound was gone.
Otherwise, check fan / alternator as mentioned above.

The fan belt was too tight when it went to the doctor a few months ago. No scrapes in the fan housing. Whine tends to either go away or become less noticeable when RPMs increase. Can't hear it in the car either.
Everything else is tight. And Jim, its an "electronic" whine. Almost like a supercharger...but not quite.

If your car is a carrera and the whine could also be described as a high frquency whistle that's most notable at idle or slightly above and it's not the item's that have been suggested it might be a dry oring on the idle set screw. Mine drove me crazy until someone else suggested i lube it and voila.

Yes. A whistle at idle and slightly above. O-ring on the idle set screw? How does that cause this noise?

i'm guessing the oring gets dry over the years and air bleeds past it causing the whistle

My car gave off a distinct whine when the alternator bearing was going out. It was more notable when at idle and hard to hear over 2 grand. I eventually sent it out to get rebuilt by a local alternator shop and the whine went away.

Good luck!

I have a similar noise, but only at low ambient temperatures. I'm sure the elasticity of belts changes with outside temperature?

Hmmm...could be three things. It is pretty cold here right now. I guess at 65k the alternator is ready for a rebuild and I am sure the o-ring is dry. Two more things to my list of stuff to do.

mine has whistled at idle since i drilled my airbox

It's the water pump gone south!

Mine was wining and turned out to be the heater motor in the engine compartment.