[MoBimmaMoProblems]

Hello guys...

Have recently bought a 2005 318i E90 ES.

Vehicle is driving smooth, everything working as it should.

Recently after leaving the engine on for at least 20 mins I get a loose rattling sound that only seems to disappear when accelerating. This is consistently happening everytime.

I had the vehicle booked in at the dealership for a recall but in typical fashion they couldnt replicate the issue. I think they just didnt have the car on for long enough.

Please can anyone shed some light on this.

I have a video of the issue. Please find the video on the link below.

https://drive.google.com/file/d/12JZ...ew?usp=sharing

Any guidance or suggestions would be appreciated.

[E92_William]

That sound would drive me nuts. Check if you can heat it more in the belt area I would think it's a bearing or something there. What happens if you turn off the ac compressor while running? I would take off the belt regardless and run it and see if it still does it to rule out if it's an external accessory

[MoBimmaMoProblems]

Thanks E92 William

Which belt do you mean? I tried to mention this to the dealership but they said the vehicle is chain driven so it wouldnt be that.

This noise happens regardless of whether the AC compressor is on or not.

Yeah the noise is driving me nuts, starts quiet and gets louder the longer you drive as well.

Some people have advised its the alternator belt but Im really not sure at this point, Im not very mechanically minded.

[E92_William]

I mean the serpentine belt. Since this car has an electric water pump the only concern of running it without the belt for a bit is no battery charging or power steering. Worth a try to see if it stops