Buzzing noise

Discussion in 'Hyundai Kona Electric' started by JohnEEngineer, May 18, 2021.

  1. My Kona Electric started making a buzzing sound, which becomes louder as I accelerate above 40 miles/hour. This buzzing sound is of lower pitch than the normal high-pitch sound of the electric motor. Because it doesn't make the buzzing sound when coasting, and doesn't change when turning, I assume it's in the drivetrain (electric motor, reduction gearing in the "transmission" or any linkage from motor to the wheels). My 2020 Kona was manufactured in late 2019 (Q4); the odometer is around 7400 miles; and recalls (including the brake recall) have been performed. Other than ear plugs, has anyone with this problem found a solution?

    Did Hyundai change the electric motor design (or mounting or transmission reduction gearing or linkage) between the 2020 and 2021 years?
     
  2. What's we've done in the past is record the noise and break down the dominant frequencies in an attempt to isolate the cause. We've had reports of clicking and high-frequency electromechanical noises but no one yet has complained of a buzzing, as best I can recall over 2.5 years.
     
  3. My initial clicking noise related to a failing motor bearing eventually evolved into a highway speed drone that made it sound like a motorcycle exhaust. The noise started around 7000km,. My 2020 Kona was an Oct 2019 build, sorry I don't know it that helps or confuses things.
     
  4. mvillalta87

    mvillalta87 New Member


    Hello jhon,

    I just bought a 64kw Kona from May 2021, and when I tried it I have also noticed a buzz that goes from 30mph to 70mph approximately, and it is a continuous buzz as you also describe, have you had a solution?
     
  5. Electric Rich

    Electric Rich Active Member

    Hi, I have a mid 2019 build also. I have also noticed a noise that I would describe as a low drone at various speeds, it comes and goes but seems to be a bit more apparent these days. I too think its drive train related but its the type of noise only an owner will notice straight away, and until it gets worse i cant be bothered trying to get the dealership to acknowledge it. I have 2 and a 1/2 more years of warranty left so I kinda hope it becomes obvious by then.
     
  6. mvillalta87

    mvillalta87 New Member


    Have you tried uploading to another kona to see if it does?

    I think that the noise we hear is the same as that heard with the window down and at low speed (10-20kmh) but in this case when going faster it becomes much noisier since it manages to enter the cabin.


    Thank you for reply!!
     
  7. MSimpsonNJ

    MSimpsonNJ Active Member

    I have the exact same situation. 2020 Kona/2019 build. I hear the Wheel of Fortune sound faintly at low speeds (not all the time but often) and at highway speed I hear a low drone sound, and as you say, only an owner will notice it at this point. I brought it up at the dealer when I brought the car in for tire rotation and they said they didn't hear it so I'm waiting for it to get worse. I'm wondering if there is a visual inspection of the traction gear/motor that can be done that would reveal the problem but so far no one has been able to tell me if this is possible.


    Sent from my iPhone using Inside EVs
     
    electriceddy likes this.
  8. Do not wait! Have the gearbox oil changed (it is inexpensive), at that point any particles in the oil should initiate a gearbox replacement in warranty. If no particles, the noise should be reduced and function properly, See later posts in Repair issues and fixes sticky thread top of page;)
    Hyundai missed the maintenance frequency factor on this one item.
     
    KiwiME likes this.
  9. Electric Rich

    Electric Rich Active Member

    Thanks Eddy, I'll ask for that next time the car is in.
     
    electriceddy likes this.
  10. You might be lucky enough to have a 10-year warranty, unlike almost all of the rest of the world but just in case you don't, the message EE was trying to get across is here :)
     
  11. Electric Rich

    Electric Rich Active Member

    ok ok, i'll book it in :)
    Interestingly, when i called my dealer to get a price on changing the oil, they were very upfront about the noise possibly being caused by the motor or gearbox bearings. They also mentioned the first thing they may try, is to use an updated mounting bracket for the motor to help with alignment. I had wondered if that was possible with the first gen motor, so I guess it is.
    The noise I hear is quite subtle at this stage so I doubt I'll get a new motor out of it this time around but i will use the visit to gather as much info as I can on this 'mounting bracket, as I assume some of you without warranty, might be interested.
     
    KiwiME and electriceddy like this.
  12. Amazing sometimes how little it takes to get the service dept to acknowledge "well - there may be an issue", while at other times it is considered "normal operation". Offer to spend a little $ for a preventative maintenance, and suddenly get an honest answer.
    The oil change will definitely help, regardless if an actual replacement is required.
    Perhaps as more owners have this service done, Hyundai might actually revise the maintenance schedule accordingly.
    On a side note...the new bracket has worked for some ;)
     
  13. Electric Rich

    Electric Rich Active Member

    Well, i replaced the gear oil, just a quiet AUD305 process but worth the piece of mind.
    Mechanics said it was super clean, no metal shaving present and they gave me a sample too.
    As some have mentioned, probably worth doing in the first few years incase some parts started to wear as they settled into position or started to fail if you're unlucky.
    Fingers crossed it stays nice and clean.
     
    KonaAU and electriceddy like this.
  14. Are you able to post a photo of the oil sample and mention your odometer reading? Great to hear that the old oil was clean!

    On a semi-related note, a DIY oil change video appeared recently:

     
    electriceddy likes this.
  15. Good find, thanks for posting. Easier to understand the process in video format, and it really seems pretty strait forward.
    Maybe re-post this or add link in repair issues and fixes thread before it becomes hard to locate.;)
    I also like the referral to part# for the magnetic plugs and crush washers (Votex ACWM18) @2:54 as well as confirmation of the Redline MT-LV fluid replacement.
    Notice his record of maintenance shows a change @ ~5000 miles interval further in the video.
     
  16. Hyundai "service" didn't find a solution to the drivetrain noise in my 2020 Kona EV before I replaced it with a 2021 Kona EV (my third all electric car since 2012). So far I've been able to adapt to the remaining design quirks in the Kona EV.
     
  17. Tim94549

    Tim94549 Active Member

    I have a similar issue on my 2020 Ultimate. (Build Sept or Oct 2019). 8,300 miles. At about 7,800 miles I developed this weird thump thump thump sound during acceleration. It became more obvious at about 20 MPH and would come & go intermittently after that. (Wasn't constant - just a new sound I had never heard.) It sounded like it was coming from the rear driver side. I took it into Service. They had a very hard time hearing it right away. Initially they diagnosed as "front wheel bearings" ... which I had my doubt. After ordering & replacing, the noise was still there. (they left the new bearings in thankfully.) They kept the car overnight to further diagnose. The following day they put some sound sensors or something around various components and said they recorded the issue & sent to Hyundai. Their diagnosis was that it's the "Reduction Gear" - and ordered the part for replacement. That was 3 weeks ago and the noise has gotten noticeably more evident. I am due to take it in TOMORROW for replacement. I will post an update after tomorrow.
     
    electriceddy likes this.
  18. You got a reduction gear in three weeks?!
     
  19. Electric Rich

    Electric Rich Active Member

    Hi all, I have attached a picture of the oil sample. It was a dark grey colour. I let it sit in the jar for a while to see if any sediment fell to the bottom, then gently emptied it to inspect the bottom of the jar. Abosulutely no sediment or even specs in the jar. It was so clear of 'bits' that I wondered if the sample is just new oil, but they did give me a fair bit so hopefully not.
    PS my car has done just under 20k KM 20220506_111515.jpg .
     
    Wildeyed and KiwiME like this.
  20. Tim94549

    Tim94549 Active Member

    So I have an update. Took car in on Wednesday of this week. They kept it for 2 days. They replaced the "Reduction Gear" and fresh oil, under Warranty. The annoying noise is GONE ! Back to a perfect car again. :) As far as how fast they were able to get this? Not sure. But we do have like 5 Hyundai Dealerships in the SF BAY area.
     
    Kirby34 and Wildeyed like this.

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