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Discussion Starter · #1 ·
Just got my Volt a few days ago and did my first solo drive in it today. I noticed when I accelerate or step on the brakes to decelerate, there is an extremely high pitched sound, somewhere I think around 16-17kHz. It sends shivers down my spine. Is this a normal thing?? The sound is something like the sound of a rotary saw (though not nearly as loud), and perhaps a dog whistle. Has anyone else come across this problem?
 

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Is yours a 2014? I have a 2012, and also have some very high pitched whines that are unpleasant - many folks can't hear them at all, which I think is just a a difference in hearing acuity, not that different cars make different noises. I was kind of hoping that they'd improved the noises in the 2014s.

In my 2012, it's worst when in Mountain Mode and during Regenerative Braking. In pure electric mode I can hear it but it's fairly quiet and I can often tune it out.

If you have a "rotary saw" or "buzz saw" like sound, that may be a different problem with some bearings that are prone to failure.
 

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Discussion Starter · #3 ·
Thanks for your reply. It is a 2014. What I meant by the saw is that high whirring sound that is really an overtone. I actually called my dealership and will be taking it in next week to see if they can hear it too.
 

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Just got my Volt a few days ago and did my first solo drive in it today. I noticed when I accelerate or step on the brakes to decelerate, there is an extremely high pitched sound, somewhere I think around 16-17kHz. It sends shivers down my spine. Is this a normal thing?? The sound is something like the sound of a rotary saw (though not nearly as loud), and perhaps a dog whistle. Has anyone else come across this problem?
how much time did you spend test driving the car? Hopefully enough to have experienced this already.....
 

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Discussion Starter · #5 ·
It's not the sound when you go from a stop and step on the gas-- that sound is a sound which slides up in frequency, though at a lower frequency than this other sound, and that sounds totally normal and acceptable to me, like a electric machine starting up. This other sound is much much higher in pitch and starts after that other sound is done, when I'm going 30-40 or so. I haven't done much highway driving yet, so I'll see if it's still there when I go at higher speeds.
 

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It's not the sound when you go from a stop and step on the gas-- that sound is a sound which slides up in frequency, though at a lower frequency than this other sound, and that sounds totally normal and acceptable to me, like a electric machine starting up. This other sound is much much higher in pitch and starts after that other sound is done, when I'm going 30-40 or so. I haven't done much highway driving yet, so I'll see if it's still there when I go at higher speeds.
In my 2012, when I start driving from a stop, I also hear the whine which increases in pitch (and I believe then goes out of my hearing range). When I hit 30-40mph or so it gets quieter overall. (I don't have a 2nd noise like you do, or if I do, I can't hear it).

Try this: put your car in HOLD mode to get the engine running, then switch the L-Low mode and see if the sound is worse as you decelerate from 60mph. In my 2012, when the engine is running and I decelerate is when the sound is the worse and kind of makes my teeth ache.
 

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It's not the sound when you go from a stop and step on the gas-- that sound is a sound which slides up in frequency, though at a lower frequency than this other sound, and that sounds totally normal and acceptable to me, like a electric machine starting up. This other sound is much much higher in pitch and starts after that other sound is done, when I'm going 30-40 or so. I haven't done much highway driving yet, so I'll see if it's still there when I go at higher speeds.
There are normal transitions that take place above 35 mph that you may be hearing. once you have reduced your acceleration, the car starts up the second electric motor (mgb) and slows down the first one (MGA). There are lots of spinning parts, all moving at differernt speeds, with some interactive harmonics. There are also sounds coming from the power block, normal power electronics sounds. You have much better hearing than I do. Many years ago a friend told me that when he thought his car was making a funny sound, he would turn up the radio- .... saved him a lot of repair shop trips and his car eventually rusted away before any mechanical failures.
 

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Some people here have mentioned a faulty power inverter could cause high pitched frequencies. I think the high pitch is fairly common and I recall hearing it on a test drive but not on the one I purchased. I do have various high pitches that happen when accelerating hard but to me it is just normal electrical motor and electronics sounds and not something constant.
 

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Just got my Volt a few days ago and did my first solo drive in it today. I noticed when I accelerate or step on the brakes to decelerate, there is an extremely high pitched sound, somewhere I think around 16-17kHz. It sends shivers down my spine. Is this a normal thing?? The sound is something like the sound of a rotary saw (though not nearly as loud), and perhaps a dog whistle. Has anyone else come across this problem?
If you record and post the sound it might help other members to identify if as one they have heard from their own Volts.

KNS
 

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Do you remember being able to hear an old CRT style TV in the next room even if the sound was turned off? That was the horizontal scanning frequency of around 15 khz. This Volt noise sounds like that. Most people couldn't hear the TV 15kHz sound so if the Volt sound is a little lower like 13kHz, that would explain why more people seem to be able to hear it.
 

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Discussion Starter · #15 ·
Well, I tried to record the sound with my iPhone microphone today and it didn't really work. I think the sound isn't loud enough. I also tried to pinpoint it more. It is most apparent when I'm braking, when the car is under 40mph. When I am accelerating, it's audible from around 10-40mph. When I was on the freeway above 40mph, I didn't hear this sound.

My husband is also able to hear the sound. It's faint, high pitched, and metallic sounding. I'm going to go into the dealer and see if they can hear it too, and determine whether it's normal or not.
 

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Well, I tried to record the sound with my iPhone microphone today and it didn't really work. I think the sound isn't loud enough.
I certainly wouldn't call it loud. Audible yes, but not loud - might be troublesome to get a good recording of it without proper equipment. That said, maybe it's also possible that it's outside of the frequencies it'll bother to record? Especially if it's using a lossy encoding, like mp3s are.
 

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Discussion Starter · #17 ·
I looked up the iPhone frequency response and it claims to be 20-20k. But the sensitivity falloff is probably pretty sharp at those high frequencies. Hopefully lathe techs at the dealer will have "young ears" and be able to detect it.
 

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Discussion Starter · #18 ·
Update: Took into the dealer and the service people checked with Chevy about the noise (audible to the tech when I went for a test drive with him). Apparently the noise is "normal"-- some cars have better insulation than others, and as of right now, no way to add additional insulation. Hopefully Chevy will come up with something later.
 
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