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View Full Version : Vibration/humming noise only at 2000rpm (in 1st and 2nd gear only)



sokoro717
10-01-2020, 04:10 AM
New member and first post here, driving a 2014 Audi S7. Whenever I accelerate from a stop I hear a vibrating/humming noise every time the RPM gets right around 2000RPM (not super loud the radio has to be off to hear it - I'll upload video if I can). This only happens at 2000RPM right before it shifts into 2nd gear (recently Ive started to hear it faintly from 2nd gear into 3rd gear at 2000RPM as well). But other than those two gears I don't hear the noise.

Video LINK: https://drive.google.com/file/d/1I_n4PuN59yLlCmIE6kcUHt-RLpQ-Mp98/view?usp=sharing

Background Info: I bought a 2014 Audi A7 in December 2019 and noticed this same humming/vibrating noise around 1800-2000RPM shifting into 2nd gear. When I took it to Audi Fort Washington one of their experienced mechanics said the noise was coming from loose exhaust flex pipes. He stated this was common for the A7 model once the cars been worn down a little (This A7 had 88K miles on it). He said the loose flex pipes weren't causing any damage it just makes the humming/vibrating noise when you shift into 2nd. So I opted not to fix it right away and eventually traded the car for my current 2014 S7.

When I took my current 2014 Audi S7 into the same Audi (different mechanic this time - not sure if he saw notes from my previous cars issues) this mechanic claimed that noise may be a result of my motor mounts leaking dry (hydraulic fluid leaked out) and would need to replace both. He didn't mention the flex pipes like the anticipated based off my last Audi's diagnosis.

LONG STORY SHORT: Has anyone else experienced this issue? I searched threads and didn't quite find a good match. The entire engine isn't shaking/clunking like you see with normal motor mount issues and it only vibrates/hums at 2000rpm and then it shifts gears and it's fine so I'm not confident in the diagnosis. Would hate to spend $1,200 for new motor mounts and the noise still occur and vis versa with the flex pipes.

Also.. if It isn't the motor mounts causing this issue and I choose not to replace them right away is there any potential damage that can be done? What does the hydraulic fluid do ? I read it is just a comfort thing.

daytona rs7
10-01-2020, 04:21 AM
it is weird you have a similar complaint on 2 different cars.

unfortunately, you cant really assume its the same problem. that would be quite a coincidence!

motor mount failure could certainly cause a humming sound base don RPM (engine harmonics). fortunately they are also a rather easy thing to diagnose. leaking, as the tech mentioned, is a visible diagnosis that they can show you. additionally, the mounts have sensors in them that will throw code when scanned with the proper tools.

FYI, a failed mount is a rather common problem, so i wouldn't be to skeptical of the diagnosis.

sokoro717
10-17-2020, 01:18 PM
added a video. Mind watching and telling me if you think the sound is from bad motor mounts?