Need help with a identifying source of a different kind of high pitched noise….

[Jau24]

Thanks in advance for your help. I've got a high pitched whine that I could use some help identifying. It's not the balloon squeal version under hard acceleration (I have that too). This one appears at around 35mph and remains a constant high pitched tone until I slow down to under 10mph; at that point, the sound slowly descends and goes away until I speed up again. The noise resembles the hum of a fluorescent light, except high pitched. Not exceptionally loud, but annoying once you've heard it once and realize it's always there. I've brought it in to service, and they have a hard time recreating the noise on demand. I've attached a video where you can hear the sound start and stop several times. (you may have to really turn up your speakers to hear it) In the video, you can hear it start at second 3, then decline around second 8. Much more noticeable starting at the 18 second mark and declining at the 21st second mark. Goes on one more time at the 53 second mark and declines at the end of the video. Any thoughts on what this could be?

 

[jhs_7645]

I can’t help with identifying it, all I can say that I do hear it, and it’s not a sound I’ve ever heard. It’s especially interesting in that the ‘whine’ doesn’t seem to correlate with power output or speed. I think taking this video to your service center should help them diagnose the issue.

 

[wycolo]

Hah! You call that a noise; I'll show you some noise: Whirlies, Cicadas, etc. Luckily, NO Rumblies (they are really bad news!).
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[islandbayy]

Thanks in advance for your help. I've got a high pitched whine that I could use some help identifying. It's not the balloon squeal version under hard acceleration (I have that too). This one appears at around 35mph and remains a constant high pitched tone until I slow down to under 10mph; at that point, the sound slowly descends and goes away until I speed up again. The noise resembles the hum of a fluorescent light, except high pitched. Not exceptionally loud, but annoying once you've heard it once and realize it's always there. I've brought it in to service, and they have a hard time recreating the noise on demand. I've attached a video where you can hear the sound start and stop several times. (you may have to really turn up your speakers to hear it) In the video, you can hear it start at second 3, then decline around second 8. Much more noticeable starting at the 18 second mark and declining at the 21st second mark. Goes on one more time at the 53 second mark and declines at the end of the video. Any thoughts on what this could be?

Variable speed cooling pump or possibly one of the fans. As you accelerate, more heat buildup, and the rpm of these comes up to full speed. Since your at about 70*F, it's borderline not needing the active cooling, and the airflow from outside is enough to cool the systems. Also not hot enough for them to remain on constantly. Do this, after a HARD HOT RIDE, just pull over and park. You will hear the noise while parked for a few minutes. That will confirm what I say.

Above is based on personal experience and experimentation, though I may be wrong, that is my opinion.

 

[yobigd20]

that's a new one I haven't heard. email that video to your service rep they can forward it to HQ and schedule you to bring it into service. I've had more luck that way vs dropping it off and trying to recreate. at least you have proof now that can be replayed over and over.

 

[apacheguy]

Variable speed cooling pump or possibly one of the fans. As you accelerate, more heat buildup, and the rpm of these comes up to full speed. Since your at about 70*F, it's borderline not needing the active cooling, and the airflow from outside is enough to cool the systems. Also not hot enough for them to remain on constantly. Do this, after a HARD HOT RIDE, just pull over and park. You will hear the noise while parked for a few minutes. That will confirm what I say.

Huh, at 70? I've never seen active cooling kick in until above 100 F in 2+ years and over 40 K and living in a relatively warm climate. Sure cooling *might* trigger if you are repeatedly flooring or SpC, but during normal driving, I've never seen it at those temps.

 

[islandbayy]

Huh, at 70? I've never seen active cooling kick in until above 100 F in 2+ years and over 40 K and living in a relatively warm climate. Sure cooling *might* trigger if you are repeatedly flooring or SpC, but during normal driving, I've never seen it at those temps.

I'm saying it's the variable speed pumps. Active cooling is when the AC compressor kicks in. I'm not saying it's the AC compressor. That only happens for me when its 90+ out or I'm Supercharging. But that sound is just like my cooling pumps. Intermittent spin up and spin down. Could just be my old car though..... I'm at 44,000 miles.