MG4 SE rattling noise over 100 kmh

[Diggsy]

There are two hinges at the rear of the entire thing. The rattling stops if I applie a little pressure there while it's in place. Are these the hinges you are talking about? Look at the red circles

Yes that’s them. The first time I fixed mine was by adding foam there, only to later find I needed some around the light fitting.

You can apply thicker foam at the hinges as there’s more space

 

[OriginalBigAl]

Do RHD models have the same cabin rattles as LHD models, apart from the sunglasses holder?

 

[gravity]

Hello everybody,
I'm writing from Italy. I own a red MG4 SE since last dec 2022 and I'm loving it. I had the oil leak issue, resolved after ONLY 5 months...Everything else was flawless...until this last weekend. We went for a ride to Tuscany and right after passing 100/105 kmh on the highway, a rattling noise came up coming apparently from the passenger door area. I couldn't understand if from the inside, under o elsewhere. Checking parts roughly nothing seems to be loose or damaged...anyone else maybe? Thanks for your attention. cheers

Giacomo Ardesi

Hi Giacomo,

I am new here so forgive my amateurish writing:

Did you manage to identify the source?

The rattling you hear, I hear in my MG4 SE as well. It used to starts at 80km/h. I took the car to my dealer for this and he could not hear it/ find the source. Which may suggest, it is likely a random fault related to the assembly.

Recently, I did a general sound damping/acoustic treatment/noise blocking using Alubutyl, foams and rubber seals. It was the first step to HighRes audio upgrade (speakers, amps, dsp). The car feels quieter, music sounds more detailed.

However, since the car is quieter, the same rattling noise is now already noticeable at 60km/h. It appears to be wind noise of some sort; and it drives me nuts.

I am musician and my trained ears cannot ignore the effect of that rattling sound on an otherwise detailed music playback from the MG4 infotainment system.

The MG4 Infotainment, in my opinion, is well built and probably high resolution audio compatible. I play FLAC from USB and Tidal for streams. Music playback sound best at volume level "20 -23" on the MG4 infotainment music player with EQ, loudness and SVC turned off. This is likely something to do with the energy saving of the built-in amplifiers at lower volumes. Above "24" results in distortions. Again this is just my ears could be different for others.

I will definitely benefit from eliminating this rattling noise and useful suggestions from the community will be greatly appreciated.

 

[Ian Key]

Start by removing everything out of the car that's not fastened down even the tools from under the boot floor.

Check the rear seatbelt buckles aren't knocking against the plastic trim. A piece of self adhesive black felt stuck onto the trim cures this.

Are the rear seats rattling against the catches?

Have a look under the car to see if any of the under-tray panels have a bulge and are catching the wind and vibrating

 

[gravity]

Start by removing everything out of the car that's not fastened down even the tools from under the boot floor.

Check the rear seatbelt buckles aren't knocking against the plastic trim. A piece of self adhesive black felt stuck onto the trim cures this.

Are the rear seats rattling against the catches?

Have a look under the car to see if any of the under-tray panels have a bulge and are catching the wind and vibrating

Hello Ian,

Thanks for the suggestions, I have the opinion that for this specific rattle, unfortunately, your suggestions have already been checked. I even removed the entire glove compartments, and the door trims to see if I would find some shaky plastic. I did not find one that would respond to wind/vehicle speed in such a consistent manner. The seats do not rattle, the seatbelt hooks are also out of the question. I think only those who have experienced this exact issue will understand it.

Outside, having another trained ear, stick a head into the space behind the glove compartment with a touch light and try to listen and poke fingers, while the car is driving at 80km/h.

 

[siteguru]

Have you tried adding sticky-backed felt around the aircon vents behind the glovebox? (Some have reported that the vents vibrate against the plastic trim, and adding the felt stops this as they vibrate against the felt instead).

 

[gravity]

Hi Siteguru,

I did read this months ago and it was the first thing i tried. I was shocked it didn't work, given there is even a youtube video about it.
So no, this is sadly not the solution to the speed-dependent rattling that @Ardez and myself tried to describe. Maybe I will try to record it and post it here.

I even reached deep to the air inlet door for the MG4's HEPA filter and lubricated the plastic hinges, just in case it had enough play to allow rattling. Air flow into the filter does not depend on AC being turned on or off. The air inlet door blocks or allows filtered outside air into the cabin in a free flow manner.

I did find a couple of circular opening/cuts in the car body and sound damping material behind the glove box on the wall ajacent to the passenger tyre well (left-hand drive). It opens directly into the "dirty" wind path of the car frame. As the car cuts through the wind the aerodynamics of the body shape, channels the air current the best it can via different slots in the car frame.

In fact, I thought someone in the assenbly line forgot to plug the unused holes for this MG4 SE. (See photo)The black acoustic form is my attempt to plug the big hole in question by stuffing it. Yes this slightly reduced the loudness of the rattling, but it was a very tight corner to reach. So I do not think I achieved an air tight seal. A better seal would be from immediately outside the metal (not reachable). My reasoning is as follows: If the air from this or any other hole causes something around it to rattle, I will like to find the rattling piece and glue/tape it down or secure it some how. I have given up on stopping the wind from getting in. This is why I have turned to this community for help.

 

[tsedge]

My boot latch rattled, which was sorted by some electrical tape wrapped around it and adjusting the bungs in the bootlid.

 

[Diggsy]

Have you applied pressure to the rear of the interior light housing when you hear the rattle? It’s simply astonishing how the rattles from that area travel around the car.

Press upwards on the area just behind the SOS button, and see if that helps. If it does, then you’ll have to take the housing out and apply felt or foam to all of the areas where plastic meets plastic.

 

[gravity]

Have you applied pressure to the rear of the interior light housing when you hear the rattle? It’s simply astonishing how the rattles from that area travel around the car.

Press upwards on the area just behind the SOS button, and see if that helps. If it does, then you’ll have to take the housing out and apply felt or foam to all of the areas where plastic meets plastic.

Yes i did try the interior light housing and the glass holder to no avail. I have researched this and other cabin noise here on this forum and elsewhere for sometime now. It appears only @Ardez reported a similar experience.

I did manage to reduce the loudness of the rattling noise as I'd hinted in my earlier post. I believe it is not a resonance related noise, rather it has all the markings of an air current induced noise. It is consistent and begins at 60km/h. If the car is noise dampened and acoustically treated the rattling is already audible at this speed given the reduced noise floor in the cabin. In an untreated MG4 SE, as was my case before my noise treatment, the sound becomes loud enough to be distinguishable at about 80km/h.

 

[gravity]

[Solved]. I found the source of the speed-dependent rattling. It is an air stream, but not under the gloves compartment like I vehemently defended above. Apologies @Diggsy . First, credit goes to Burl Solomons who 3 minutes into his video . Briefly mentioned this.

The rubber trim around the little glass polygon next the side mirrors is the cause of this rattling. From the picture, it is easily observable that at the top corner, the seal does not merge/seal in a seamless and continuous manner to the dividing black vertical strip separating the window from this polygon. This result in a stream of air that one can feel on a finger placed next to the corner. That air stream rattles the edge of the rubber seal.

In my case, the noise from the passenger side was more prominent. However, upon checking the driver side trim, it also rattled, though not as loud. Hence a stereo effect, that dubiously blends in as part of "road noise". In fact, placing a finger at these points to hold the rubber seal's edge instantly kills the noise! Car instantly quieter.

Fun fact: given this is a structural problem with this standard part, chances are that an unknown number of MG4 owners currently experience this noise to varying degree and dismiss it as road noise.

Solution: I carefully filled the points in question with rubber material to seal the exposed cross-section.

 

[Tuareg]

Maybe this is causing the 'vibe' on some xpowers?

 

[gravity]

Maybe this is causing thc 'vibe' on some xpowers?

Likely, since the same rubber seal is used on all MG4 models.

 

[Diggsy]

[Solved]. I found the source of the speed-dependent rattling. It is an air stream, but not under the gloves compartment like I vehemently defended above. Apologies @Diggsy . First, credit goes to Burl Solomons who 3 minutes into his video . Briefly mentioned this.

The rubber trim around the little glass polygon next the side mirrors is the cause of this rattling. From the picture, it is easily observable that at the top corner, the seal does not merge/seal in a seamless and continuous manner to the dividing black vertical strip separating the window from this polygon. This result in a stream of air that one can feel on a finger placed next to the corner. That air stream rattles the edge of the rubber seal.

In my case, the noise from the passenger side was more prominent. However, upon checking the driver side trim, it also rattled, though not as loud. Hence a stereo effect, that dubiously blends in as part of "road noise". In fact, placing a finger at these points to hold the rubber seal's edge instantly kills the noise! Car instantly quieter.

Fun fact: given this is a structural problem with this standard part, chances are that an unknown number of MG4 owners currently experience this noise to varying degree and dismiss it as road noise.

Solution: I carefully filled the points in question with rubber material to seal the exposed cross-section.

Great to hear you sorted it! Could you perhaps post an image slightly more zoomed out so that I know where to apply pressure, in order to see if that’s a noise I have on my passenger side please?

 

[siteguru]

Likely, since the same rubber seal is used on all MG4 models.

UNlikely, as the X-Power vibe is felt through the steering wheel - it's not just an audible "feature".

 

[Coulomb]

Could you perhaps post an image slightly more zoomed out so that I know where to apply pressure,

Or @gravity, just confirm or deny that I have the right place circled below. This is from the inside of the right side of my Australian MG4 (driver's side here):

Sorry for the poor focus; it was a quick snap in a carpark.

 

[DaevM]

Luckily I have impressive tinnitus that deadens most ad-hoc sounds.... That and also spent a lifetime following advice from a mate who got a job as a Vauxhall mechanic when querying random ad-hoc noises on my old first car Triumph Herald - "turn the radio up, wait for something to fall off".... Probably explains the tinnitus

 

[gravity]

Or @gravity, just confirm or deny that I have the right place circled below. This is from the inside of the right side of my Australian MG4 (driver's side here):

View attachment 33463

Sorry for the poor focus; it was a quick snap in a carpark.

Yes. That point.