Trying to discern normal noises from abnormal.

I'm trying to determine if the whirring noise I am hearing at idle and at low speeds is a normal supercharger sound, or if it is the alternator making this noise.
I am aware the supercharger does make some noise, a whining noise when you are getting on it, but at idle should I be hearing anything at all from it? The gears?
When I first looked at the car, my first reaction to the noise was that it was the alternator.
In watching and listening to the videos on YouTube from other Riviera owners, I do hear what I think is the noise I am referring to.
(If the guy who did the 0-100 video is on this board, that was awesome.)

I intend on using a stethoscope I have to locate exactly were the noise is coming from, but thought I would get some advice as to what is considered normal beforehand.

Thanks!

The SC should be pretty quiet at idle. I'd suspect something else, like alt or pwr steering pump as possibilities.

My alternator made a whining noise before it nearly failed at around 30k miles. The diagnosis was made by touching the unit by hand. If it's very hot, it indicates a mechanical (bearings) problem.

This could also be an idler or tensioner pulley going out. How many miles are on the car?

AA wrote:

My alternator made a whining noise before it nearly failed at around 30k miles. The diagnosis was made by touching the unit by hand. If it's very hot, it indicates a mechanical (bearings) problem.

This could also be an idler or tensioner pulley going out. How many miles are on the car?

The car has 192,000 on it. I still haven't gotten used to the fact that it is not uncommon these days for cars to accumulate 200,00 miles and still be perfectly fine with many miles left in them.

I do have one idler pulley that chirps, that will be taken care of shortly.
I'm leaning towards my first impression that it's the alternator making this sound.

Take care of the pulley soon. They don't last very long after they start making noise. At your mileage, all of the idler and tensioner pulleys should probably be replaced. Most of our cars experience at least one pulley failure between 85-100k miles. I've seen 3 separate pulley failures on my car over 170k miles.

AA wrote:

Take care of the pulley soon. They don't last very long after they start making noise. At your mileage, all of the idler and tensioner pulleys should probably be replaced. Most of our cars experience at least one pulley failure between 85-100k miles. I've seen 3 separate pulley failures on my car over 170k miles.

Will do.
I plan on replacing the rest of the pulleys next summer when I thoroughly go over the car replacing belts, hoses and other routine service items.



My parts list keeps growing.

Sweepspear wrote:

(If the guy who did the 0-100 video is on this board, that was awesome.)

holmdude?? if so that is "I"