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Humming noise on High RPM

I’m living in Saudi Arabia and in a relatively small city so I got very few professional mechanics here.
I’ve Hyundai Sonata 2011 bought preowned a year before, from that day (didn’t know this issue before buying) I’m having this issue that car is making very loud humming noise on high RPM like 35000+ whether it’s still or on road, so rule out the possibility of worn bearings or other tires related issues because it’s of high RPM even on parked car and there is vibration that also increases accordingly as noise. I showed it to my usual mechanic he said immediately change the transmission fluid I said I’ve already changed then he said show it to some transmission mechanic, so I went to transmission guy he said there is no problem in transmission this sound is coming from Exhaust Manifold or something related to it, I went to the guy who deals with exhaust system he said there is no problem in Exhaust System. I keep on visiting different mechanics for this issue some said this is normal some said we don’t know keep driving like this, nothing serious, one guy told me to change Engine and Transmission Mounts as this maybe because of excessive vibration, so I changed whole 4 mounts, but still noise exists. This thing is really becoming headache for me as no one’s there to diagnose this.
Then I found a thread on this website (will give link if someone asks) stating same issue for Hyundai Sonata but for older model that is 2004, he said that the problem was in Harmonic Balancer or Crankshaft Damper or Crank Pulley Damper, he wrote the other two names in bracket and upon searching I think they are all the same (if they are different please explain), I asked to my usual mechanic he said this sound couldn’t be because of pulley, but I found on thread that the guy who explained his problem; is very similar to mine but the question is his car is 7 years old model than mine, should I go for changing Harmonic Damper?
I’m sorry for going too long as I’ve to tell the whole year story.


You or your mechanic could take the serpentine belt off and grab the harmonic balancer to see if it’s loose.

Thanks for your advise I’ll check harmonic balancer and will update here, do you have any other advise or solution for this issue?


Motor sounds ok if u keep revs under 3500? Driving at 60 mph means tach is at 2000 rpm? That means 90% of time ur motor is not noisy? Try driving lightly so revs always stay under 3500. I do.

You must be driving your car in “sport” mode to get above 3500+ rpm. I would find it normal to hear all sort of noises taking a Hyundai Sonata to such high rpms. I am not convinced you have a problem.

Actually, my friends have Sonata also, those cars don’t make noises like this, I do drive under 3000rpm most of the time but still, I feel my car little heavy while accelerating (even at 2000 to 2500rpm), it feels like the engine is putting too much force to accelerate.
I’m bit busy these days will visit mechanic soon and update here.


I’ve standard Hyundai Sonata 2011, so there is no sport mode, I agree with you on this point that sounds and noises in Hyundai cars are so normal even in every model as they started to get bit older, but this noise stands out as compare to my friends Sonata.


Have you stuck your head under the hood while a friend revs the engine to 3500 RPM’s? Be safe about it, but it shouldn’t be hard to locate the noise if doing that.

Sorry, I can’t make sense out of these statements. Perhaps you mean: The car does not seem to accelerate as it should…

Car does accelerate but it sounds/feel like engine it putting too much force to do that and going up to 3000+ a loud humming noise starts coming out of front side, and this sound came even when car is still and you hit gas.

I have no idea what you mean. You can shift above or below 3000 and the redline is probably 6000. Could it be that your clutch is slipping?

I assume this is a 4-cylinder 2.0 or 2.4 litre engine with an automatic transmission. Under what circumstances do you reach 3500 rpms? Taking off on a green traffic light, passing someone on the highway? You said that even standing still it makes the noise at 3500+ rpms. How often do you need to raise the rpms this high when you are standing still? Any way to post your sound on youtube?

OP says manual transmission.

Could be a faulty harmonic balancer, but it could be a lot of other stuff too. I’m comcerned if you approach this with a replace this, replace that approach, you’ll run out of money before you run out of guesses. First thing I’d do if I had this problem, ask the shop to take a length of garden hose or vacuum hose and use it as a stethoscope to try to isolate exactly where the noise is coming from. Then you’ll have something to go on.

Exhaust leaks can make a sound, but it is usually described as a sequences of “bang” 's sort of like firecrackers, if it is a bad leak, or a "pfft … pfft … pfft " 's if a small leak. Water pumps on the way out can make a humming sound. As can alternators and power steering pumps. That can usually be determined by remove the belt that drives for a test. Have to be careful w/the water pump tho, as the engine could be ruined by overheating if it was left disconnected for too long. Fuel injectors can make a humming noise too. Timing chains/belts and their pulley’s, tensioners, and idlers too. So you pretty much got to figure a way to narrow down the area in the engine compartment it is coming from first.

One thing you got going for you, living in Saudi Arabia you’ll have no problem to find some oil to lube whatever’s making the noise … :wink:

Yes it’s 4-cylinder, automatic transmission and I really don’t know about 2.0L or 2.4L, I tried to know it many times by looking under the hood or in other expected places but found nothing, on engine cap “DOHC 16V” is written. I’ve uploaded a video on YouTube, RPMs are going to 5000 only as car is on Park other wise they go above than that, windows glasses were up you car hear the noise, though it’s still not very loud in video, but you can hear very clearly, here is the link:

I wish I could find a professional mechanic for this issue rather than oil for lubing, lol. Thank you for your advises, it’s very difficult here to convince a mechanic to check this and that for a particular issue, they say straight away “no, that can’t be the source of problem”, but I’ll try to convince them and will update here as soon as I find any thing relevant.


It only went to 5000 RPM in park because the rev limiter will stop it there. You should not be doing that anyway. I think you are not letting the mechanics do their job if the reply it can’t be that.

I can’t hear a pronounced humming noise. Like I said before running up a 4 cylinder to above 3500 rpms, I would expect some noise that is not heard under normal driving conditions. This thing is a 6-speed transmission. Under normal driving conditions the rpms should never come close to 3500 rpms unless you hit the gas hard on green traffic light.

Revving it up to close to 5000 rpms in park wouldn’t surprise me to hear all sort of noises. Besides any vibration audible as humming, I can’t think it’s good for your catalytic converter.

By the way, if your friend’s car has a different engine the sounds may not be similar.

There is a noise, from a drivers seat video it is impossible to tell if it is engine noise or from a modified exhaust system. I don’t know the quality of service available there but dealer technicians generally have more experience with specific vehicles and may know what is needed before opening the hood.

BTW my engine frequently see 3500 to 4000 RPMs before the transmission shifts, perhaps I’m a maniac.

Actually 6-speed auto transmission normally goes to 3000 to 3500 if you accelerate little hard (little more than normal), just to accelerate little faster it’s not that odd in these cars and it’s not just about passing green light, lol. Mechanics, to whom I showed my car, none of them said it’s normal or they give-up after checking and saying leave it like that it’s normal.
I’ll update here whenever I’ll find anything relevant.