humming or zinging noise

[MiteshN]

Hi Fanatics

I am hoping someone could point me in the right direction. This is a verryyyyy long shot, as I cannot reproduce this at will. The vehicle I experience this in is an F30 320i Sport.

There is numerous times (but not in a specific scenario), where I hear a zinging or humming noise and I cannot pinpoint where it is coming from. This usually is when I start the car and drive off, but sometimes even when the car is warmed up and been driving for a while.

I have tried to get BMW to check it, but when they have had the vehicle with them they say they do not hear the noise.

It is like a high pitch zing, that lasts for about 15 - 20 seconds at a time. It does not seem to get louder with acceleration, and sometimes it is louder than other times.

Thanks in advance.

 

[Danny2]

common problem on these cars is the cam chain/tensioner assembly that can be noisy.

I have however seen a 320i manual (85000km) that upon further inspection required a rebuild and also the cam chain/tensioner replacement.

 

[MiteshN]

common problem on these cars is the cam chain/tensioner assembly that can be noisy.

I have however seen a 320i manual (85000km) that upon further inspection required a rebuild and also the cam chain/tensioner replacement.

The cam chain/tensioner was done on the car about 8000km ago.
How would one know if the car needs a rebuild? The car runs perfectly smooth and has enough power etc. There are no other issues, other than this zing I hear now and again.

 

[MiteshN]

Found this video that has the same sound:

But the sound is not there when the car switches off.

It is the high pitch that can be heard in the 1st few seconds...

Anyone have any idea what it could be?

 

[streetglow]

I get those symptoms from the gearbox no cold start.