[OzX3M40i]

Hi, I have had this intermittent screeching noise happen since 2000km. I currently have 15,000km and the noise has been getting progressively worse in duration and frequency. Driving me nuts to the point of selling it.

It will happen after the car has been parked for more than 3 hours. The noise will intermittently continue for approximately 5 minutes and then dissapear completely. It will happen every morning after being parked overnight.

It will not occur at idle, and is the same under load or off accelerator.

I have tried all driving modes, a/c off, fan belt lube, long idle, short idle.

The noise is outside the car, but can still be heard clearly with the windows up and medium music volume.

It is booked in at the dealership in another week, but thought someone may have come across this in order to help speed up the fault finding process.

Thanks

[HampshireUK]

Originally Posted by OzX3M40i

Hi, I have had this intermittent screeching noise happen since 2000km. I currently have 15,000km and the noise has been getting progressively worse in duration and frequency. Driving me nuts to the point of selling it.

It will happen after the car has been parked for more than 3 hours. The noise will intermittently continue for approximately 5 minutes and then dissapear completely. It will happen every morning after being parked overnight.

It will not occur at idle, and is the same under load or off accelerator.

I have tried all driving modes, a/c off, fan belt lube, long idle, short idle.

The noise is outside the car, but can still be heard clearly with the windows up and medium music volume.

It is booked in at the dealership in another week, but thought someone may have come across this in order to help speed up the fault finding process.

Thanks

I wouldn’t wait a week

Sound like something loose.

[TxHornX3M40iGuy]

Of all the issues I've seen and heard on this forum, that is the craziest produceable example yet. wow. I'd take it in sooner if you can. If for no other reason than it is incredibly obnoxious.

[Max Well]

That sure is an irritating noise to have had to hear for 13,000km! Had you emailed the video clip (or it's link) to your Service Advisor during this time? If not, might be helpful for them to have a heads-up to hear it before your appt as it might make for a quicker fix. Keep us posted.

[skier219]

Seems obvious that it's related to road speed based on the video, so obviously idle and/or engine RPM isn't a factor. Also seems obvious that it's external to the car and not an engine/transmission noise. Check your brake calipers and discs for a pebble, loose clip, loose pad liner, or other piece of debris. Check rotating parts under the car for something stuck or rubbing.

I don't know why you waited so long to deal with it. Given that it's related to road speed greatly simplifies the troubleshooting and this would probably be trivial for a mechanic to diagnose.

[Speedbird1]

For what it's worth, I had a very similar noise on my wife's new (2 month old) F55 MINI Cooper. Turned out to be a rock wedged between brake shield and disc on front nearside wheel (nearest the shoulder in UK). The rock must have moved occasionally because the noise changed. Took a while to locate it but certainly worth investigating if you haven't tried this already.

[MechX3M40i]

Originally Posted by Speedbird1

For what it's worth, I had a very similar noise on my wife's new (2 month old) F55 MINI Cooper. Turned out to be a rock wedged between brake shield and disc on front nearside wheel (nearest the shoulder in UK). The rock must have moved occasionally because the noise changed. Took a while to locate it but certainly worth investigating if you haven't tried this already.

Agree. I also had similar experience, and if this kind of noise happens to me again, first thing I would do is to check for any foreign objects like rocks wedged in the brake area. Also look for signs of any unusual wear/abrasion of your brake discs.

[SROC3]

wow that sound is crazy horrible......omg. I hope they get it fixed sooner than later.

Do let us all know what it was once they diagnose - I'm sure we'd all like to know what went wrong in Spartanburg.

[BMWZ4]

Man, that sure sounds like a small rock stuck in the brakes...

[383vett]

Sounds like you have a cat stuck under the fender. The dealer should be able to diagnose and fix the problem easily. Not sure how you can sell a car with that noise.

[OzX3M40i]

Thanks for the suggestions.
My car has been dropped off at the dealer today.
I had a good look around the brakes, discs and shrouds, but Nothing found unfortunately.
Not quite sure how a rock would cause this intermittent noise and completely stop after 5 minutes of driving and not return when the vehicle is warm. This info was passed onto the dealer though.
Please keep any suggestions coming in the meantime and will keep you posted of the outcome.
👍

[HampshireUK]

Keep us posted

[bmwgrande]

I had a rock stuck in my caliper not too long ago, but it didn't sound anything like that.

[freitz]

Wow that is an interesting sound. They should be able to pin point that esp with how easily reproducible it is.

[OzX3M40i]

The car is still at the dealership. They have been able to reproduce the sound, which is a start, but no idea of the cause yet. Bmw Australia techicical support is now involved.

The dealership has placed me in a X3 20i m sport, which was on the lot as a demo. They had no loaners available so very grateful, but far out I miss that m40i engine sound and power. The 20i is still a nice car but once you have tasted that m40i........

[freitz]

Originally Posted by OzX3M40i

The car is still at the dealership. They have been able to reproduce the sound, which is a start, but no idea of the cause yet. Bmw Australia techicical support is now involved.

The dealership has placed me in a X3 20i m sport, which was on the lot as a demo. They had no loaners available so very grateful, but far out I miss that m40i engine sound and power. The 20i is still a nice car but once you have tasted that m40i........

Loaner is a loaner.

Interested to hear what this sound is about.

[OzX3M40i]

BMW technical first thought it may be the water pump, as M4’s have had a similar noise problem.
It all checked out ok along with the brakes/rock stuck.
A case has been opened with BMW and they have no solution yet. They also have a link to the YouTube video I attached at the start of this thread.

My car will remain with them until it is fixed. Any other ideas would be much appreciated.

[MechX3M40i]

Just wild guessing taking the shotgun approach - have they checked the drive belts or similar? Have they reproduced the problem after letting it parked for a while and then drive? Tension of the belts changed with temp inside the hood, and changing tension could be a possible cause of why it happened only after parked for a while and only intermittently.

I had a worn alternator in an old car in the past and it sounded screechy awful like that intermittently at the start of the problem. I would suggest having a look at that too if they run out of ideas.

Do you find any correlation between your problem and whether the AC is running? If it only occurs while AC is on, then check the compressor too...

[BillD1953]

my guess ?
some bearing acting up !
20,000 miles on my M40i....flawless so far

[IXVXI]

any updates to the issue?

[snakehips]

I started getting exactly the same noise last week and I only have 700 miles on the clock! It started as just half a dozen screeches for the first minute of driving from cold but today it was for a good 5 minutes or so. But always goes away when everything has warmed up and also independent of whether throttle on or off. Maybe coincidence but this has been since I had the winter wheels put on so wondered if could be brakes rubbing when cold? No idea really. Can't get to the dealer till next week and of course when I get there the symptom will have gone away because the car will be warm. So anything the you discover about the cause would be invaluable to me!

[jmoot28]

I am also having the same issue here in Melbourne Australia, its happening only on a super cold start not using the car for a couple of days,

took the car to the dealership told me to record the sound again then bring it back total waste of time!

Even used OzX3M40i video as its the same sound.

now with added NEW sounds , engine or something in the dash started to vibratehttps://youtu.be/KHW21r98660