Noise coming from MG4 Standard's Back

[vicape92]

Hello everyone!

I have been a user of an MG4 Standard for 15 days, the car now has 450km.

I have a question about a noise I notice, it comes from the back of the car, I would say the engine area.

It is a very faint sound, it can be heard with everything turned off, neither music nor the air.

It happens to me during very gentle accelerations or when I maintain a speed of 14km/h. Always that, between 13 or 14 km/h

The sound that the next one makes, below that speed it doesn't sound at all, from then on it makes a sound like an electric motor, a high-pitched hum that is intermittent at that speed of 14kmh, from then on it is a constant sound and it seems normal to me.

What worries me is the intermittency of that sound, which is like taking the sound of the car and turning the volume up and down (it's difficult to explain)

Does it do it to you? Is it normal?
I'm worried that it could come with a problem with the transmission or the alignment of the engine and transmission or something like that.

Here I leave a link to SoundCloud where I uploaded the noise recorded.

Ruido MG4.m4a

Listen to Ruido MG4.m4a by Víctor Castro Pérez #np on #SoundCloud

on.soundcloud.com

Yo can notice it in second 6 and second 24

 

[fnegroni]

I frequently drive at that speed and never noticed it in mine. Our car park has a strict 16kph speed limit. I will keep an ear out for it just in case.

It could be something stuck to the tyres check for any debris first.

 

[DixieTGS]

Is it possible that you're hearing the pedestrian alert system from inside the car? Many people don't hear it unless a window is down. Get someone else to drive the car past you at slow speed to see if it is similar.

I think I saw a module in the boot of the car behind the right hand wheel when I had the carpet removed.

Edit: Found it

 

[vicape92]

I frequently drive at that speed and never noticed it in mine. Our car park has a strict 16kph speed limit. I will keep an ear out for it just in case.

It could be something stuck to the tyres check for any debris first.

It only occurs between 13 and 14 km/h. The noise is very low and hard to hear. I hear it when I'm driving in a quiet environment. Thank you very much. If you can check, is yours also a Standard model?

Is it possible that you're hearing the pedestrian alert system from inside the car? Many people don't hear it unless a window is down. Get someone else to drive the car past you at slow speed to see if it is similar.

I think I saw a module in the boot of the car behind the right hand wheel when I had the carpet removed.

It is not the sound of the pedestrian alert, I do hear it from inside the car but I identify it correctly, this is another noise that comes from another area

 

[siteguru]

The pedestrian alert system is the same in all MG4 models, and located in the same place. As such, if it is the PAS then the model variant doesn't matter.

To be honest though I've never noticed the PAS in my own car. (SE SR = Standard).

 

[ReintjeWA]

I think you can hear the pedestrian alert system faintly in the background as a constant in your recording, so I would wager to say it's not that. If I'm listening to the right sounds, it sounds indeed to me like something spinning non centrical. Like spinning a ring around your finger in the air, that sort of noise.

I think I'm most confused by the noise being at a certain speed, I would think that if it was the motor or transmission it would be a more persistent sound across different speeds, if it was an alignment issue.

I agree with fnegroni to check the state of your tyres first, but after that perhaps a visit to the dealership wouldn't be completely out of order.

And welcome to the forum!

 

[vicape92]

I think you can hear the pedestrian alert system faintly in the background as a constant in your recording, so I would wager to say it's not that. If I'm listening to the right sounds, it sounds indeed to me like something spinning non centrical. Like spinning a ring around your finger in the air, that sort of noise.

I think I'm most confused by the noise being at a certain speed, I would think that if it was the motor or transmission it would be a more persistent sound across different speeds, if it was an alignment issue.

I agree with fnegroni to check the state of your tyres first, but after that perhaps a visit to the dealership wouldn't be completely out of order.

And welcome to the forum!

I wish I could hear what the sound of another Standard MG4 is like, maybe the sound persists at higher speeds but is only audible between 13-14... sometimes 16kmh. Maybe at those speeds you can't hear it because the engine is turning so fast? To me it sounds like something is off-centre, but I went to the shop on Friday and they told me that the sound is normal. At the garage I was told that when the power delivery to the engine is low it makes these sounds. I don't know if I believe it, the mechanic didn't seem to have much of an idea.

 

[ReintjeWA]

I’ll see if I can record mine tomorrow, where did you place your microphone? I’ll try to replicate what you did as close as possible

 

[vicape92]

I’ll see if I can record mine tomorrow, where did you place your microphone? I’ll try to replicate what you did as close as possible

I put the phone to record in the back seat of the center of the center. Thank you so much for your help!

 

[ReintjeWA]

I just thought of a quiet place where I could test and figured now would be the best time so here are two recordings. Same iPhone 15 Plus, but one with the Apple voice recorder and one with Rode Reporter App. Both are runs at 13-14 kph, with acceleration to 30 kph and then back to 0 kph at the end.



I have listened a few times and I have to say, I don't hear it. I've made the files available for download (I think) in case your mechanic wants to hear what an MG4 should sound like

 

[vicape92]

I just thought of a quiet place where I could test and figured now would be the best time so here are two recordings. Same iPhone 15 Plus, but one with the Apple voice recorder and one with Rode Reporter App. Both are runs at 13-14 kph, with acceleration to 30 kph and then back to 0 kph at the end.



I have listened a few times and I have to say, I don't hear it. I've made the files available for download (I think) in case your mechanic wants to hear what an MG4 should sound like

I don't hear it either, I imagine my car came from the factory with a fault. In your recording you can hear the wind more but I think it is because your car is quieter than mine, with this you confirm that it has come defective.

I'll have to ask them to repair it, let's see if they know how to do it at my garage, because if they didn't know how to diagnose the problem... I'm afraid to leave the car with them.

Thank you so much for your help!

 

[ReintjeWA]

I don't hear it either, I imagine my car came from the factory with a fault. In your recording you can hear the wind more but I think it is because your car is quieter than mine, with this you confirm that it has come defective.

I'll have to ask them to repair it, let's see if they know how to do it at my garage, because if they didn't know how to diagnose the problem... I'm afraid to leave the car with them.

Thank you so much for your help!

Happy to help mate, hope you get it sorted

 

[vicape92]

I have managed to test this afternoon a unit of a MG4 Standard manufactured 1 month after mine and it makes practically the same sound, perhaps it is a little less noticeable but it does so with what I conclude is normal

thanks a lot

 

[securespark]

Is it possible that you're hearing the pedestrian alert system from inside the car? Many people don't hear it unless a window is down. Get someone else to drive the car past you at slow speed to see if it is similar.

I think I saw a module in the boot of the car behind the right hand wheel when I had the carpet removed.

Edit: Found it
View attachment 33485

I'm no sound engineer (good job, because I suffer profound deafness at mid and high frequencies!), but I probably wouldn't put pedestrian alert modules inside the car..........!

 

[DixieTGS]

The words on the box say "pedestrian alert control module". Perhaps a couple of the wires go to a speaker or 2 somewhere? The bracket looks quite chunky, so maybe it uses the body panel as the speaker diaphragm, but then you wonder about the location - surely front left would be the most useful location for pedestrians with RHD car .