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Sound from my '07 Cobalt SS

I purchased this car this past summer as a GM Certified Pre-owned vehicle with 9,000 miles on it. Worked great, no problems till about 2 weeks ago. Driving down the high about 70mph, I noticed an odd sound coming from the engine area. It’s sort of a high pitched whine. I’ve since driven the car a bit to get a better background of information about the sound. It only occurs at highway speeds when you step on the gas and is intermittent in occurence. I took it to the dealer and they said nothing was wrong with it. I’ve had multiple other people who are car-buffs go for a ride and they all tend to think it’s the supercharger. My brother (who is a mechanic) said most likely either a bearring was going bad or the supercharger isn’t getting oil. Since the dealer won’t do anything about it, what should I do. The car is still under bumper-to-bumper warranty through this July. Any advice is greatly appreciated.

Without hearing it I couldn’t tell you for sure, but I was thinking a bearing before I read that far. I think they are on the right track. I would say it could be a low quality bearing, but if it just started making this noise, it’s a sign of impending bearing failure.

Of course the GM dealer is going to try to weasel out.

Does it sound almost like a dentist drilling teeth? Best way to pinpoint these things is with an ultrasonic stethoscope. If it’s going bad, that bearing will sound like it’s full of cornflakes. Get an independent shop to verify this - GM dealer will always say it’s A-OK right up to the point when it lets go.

Have you tried a Cobalt specific forum? is the first one that appears on a google search. they may have more knowledge than we do

thanks… i’ll check that out too