2019 Kona EV Motor Noise Issue

It seems that early Kona EV models are plagued with some transmission and electric motor issues.
I used to be into mechanical engineering and omission of magnet / magnetic plug to collect metallic debris is something normal in transmission design. The original problem seems to be either underdesigned components, bad materials/ workmanship, bad planning for maintenance or combination of those factors.
Of course having a magnet helps a bit, but is not key.

 

Hello,
I have the same problem...
12.000km and the sound is getting worse and worse.. Especially on first regenerative braking..
Tomorrow i will call the dealer
My car is only 4 months old

 

I'm almost at 3 years. I find that I can't tell anymore if it's noisy or not. I've become accustomed to the noises. Sometimes I suspect that it's louder than it's ever been but then I doubt myself. I know that nobody in my dealership would have a clue about what's normal or not. I suppose the only way to check would be to take an unsold model off the lot for a test drive.

 

Its deffinitly a knocking sound.. It started since october when temperstures dropped below 10 degrees.
But i dont understand how Hyundai doesnt solved this in 2022 model
I will come back after I get an answer from dealership

 

So your dealer didnt solved the problem for 3 years now?

 

No, no. I've never complained or had anyone take a look at it. I'm saying that because I'm living with the car day after day any slow degradation towards "noisy" may well have gone unnoticed by me. It's tough to remember what it sounded like 3 years ago.

I know my regen sounds exactly like honing a knife on a grinder: metallic and loud. Is that "normal"? I know there's definitely noises from the motor beyond just electric motor sounds. Is that "abnormal"?

 

How many kilometers has it?
Why you didnt report it to dealer? Sorry for my bad english

 

36K km. Apparently I'm not making my point clear. I just don't KNOW if my car's noisy because I have nothing to compare it to. Nothing sounds broken or wrong it just makes the sounds it makes.

 

This is the knocking noise when deccelerating

 

Ya, I'm pretty sure I don't have that underlying knocking noise although all the other noises are familiar. I occasionally notice a bit of the Wheel of Fortune knocking at very low speeds on quiet pavement.

 

Yeah ... that's not good.

 

You know, I've got to say that I don't listen to that (and the other examples) and think, "Yeah, that's not good." To me it just sounds like something rotating, reciprocating or meshing gears. I'm not sure I'd find it alarming at all. Now, if my car had never made the sound previously and it suddenly did I might, might think about having it checked. More power to you getting it looked at. Perhaps my standards for noises are just too generous? Maybe I'm driving a time bomb?

 

Lol, hopefully not! For context my job for several years was troubleshooting rotating industrial machinery and I've learned to discern certain issues when listening even though it may just sound like a jumble of noise. The knocking seems present in Bogdans19's video.

Engines almost always knock from multiple sources like the crank, rods and pistons even in a normal wear condition and it's nearly impossible to hear anything else but an electric motor and gearbox should not make that noise. Knocking in this case can only come from defective bearings or perhaps a worn spline.

 

My car was in for the main battery replacement this week. I asked for the oil in the reduction gearbox to be changed and for the used oil to be returned to me. I shook the used oil vigourously and poured a sample into a ziploc container. This is a single weight (SAE 70W) GL-4. It has blackened for sure but I see no sign of metal particles with an inspection light shining through it and I do not have the wheel-of-fortune noise. Mine is a Dec. 2018 build with 18K km.

 

There are no obvious visible particles because they have been circulating continuously and by now are ground down to dust, making the oil black. You will be able to tease out some of that dust with a magnet as I've done here at 19,000 km. Larger particles are what you want to see but caught by a magnet before they've had the chance to damage the bearings.

 

I've stirred a generous sample slowly with a magnet and found no visible difference between that and stirring with a non-magnetic rod. I guess I'm not that worried at this point but I'm glad to have taken your advice to change the oil and will do so again in another couple of years.

 

The example I've shown in the image above took hours to achieve with a strong magnet. Dust-sized particles are not highly attracted to a magnetic field. But larger particles freshly shed off the gears will stick to a magnet when they are very close by.

I wish all owners would take the advice because every example will have black oil in it.

 

If the oil is black you're saying that's indicative of metal contamination caused by an inherent problem with the drive train. If that's so then what good does changing the oil early and/or frequently do? Shouldn't the drive train be fixed as a solution? And is black oil a definite indicator of malfunction and therefore a sign of trouble that is inarguably persuasive to, say, a dealership you're trying to get a replacement from?

 

One opinion from the peanut gallery: in a perfect world with honourable folks willing to not hide behind the boilerplate language of any warranty, the root problem would be fixed. But, in my world, I sold my wife on the idea of swapping the oil and getting some magnets involved as a way to try and prevent the ticking noise issue from presenting itself in the first place.

 

The black oil is due to normal wear in combination with the absence of particle filtration. It seems that Hyundai/Mobis/Transys consider this to be an acceptable operating condition for the gear reducer in this consumer product. It's to their advantage that automotive gearboxes require only a laughably short life compared with industrial expectations that would never tolerate running such contaminated oil. Dealers are simply not technically equipped to understand the implications of forensic details such as this.
The downside for the consumer is that the statistical risk of failure will be higher than if they had included basic filtration like every other EV manufacturer does.

Hyundai has created their product with eyes wide open as to the risk and seem to be happy to replace gearboxes now and again without that prompting a TSB. For a consumer who wishes to avoid any unnecessary interaction with their dealer and/or loss of use of their EV, changing the oil seems to be the more pragmatic approach rather than to convince a sleeping giant to change.

I think I mentioned it once or twice in the other thread but we don't really have any evidence that this will prevent that problem. I believe however owning a 2020 or later will reduce the chances considerably because not only has the motor been updated but according to one source the reducer as well. But the reducer is still missing magnetic filtration.