[X3MDG]

https://vimeo.com/1009456345?share=copy

My 4 series has started making a metallic rattle coming on and off the throttle (gently) in first and second gears.
It’s not related to road surface. Only light throttle inputs and not present above 20mph.
Anyone have any idea?
Thank you!

[cfm56d7b]

Can you provide more details: engine type, mileage, prior maintenance history?

[Wires]

When you get in and out of the throttle, the engine will rock on the motor mounts. Maybe the mounts?

It's at such a low frequency that it doesn't sound like it's internal to anything rotating (engine, transmission, driveline). Those would have sounds matching RPM or road speed.

[X3MDG]

Originally Posted by cfm56d7b

Can you provide more details: engine type, mileage, prior maintenance history?

2018 440i B58, 50,000 miles, full main dealer service history (at recommended timelines)
Thank you!

[X3MDG]

Originally Posted by Wires

When you get in and out of the throttle, the engine will rock on the motor mounts. Maybe the mounts?

It's at such a low frequency that it doesn't sound like it's internal to anything rotating (engine, transmission, driveline). Those would have sounds matching RPM or road speed.

This was my initial thought too. Just found it a bit odd it doesn’t do it at all at higher speeds when I’m rapidly accelerating and lifting off the pedal.

[Wires]

Originally Posted by X3MDG

This was my initial thought too. Just found it a bit odd it doesn’t do it at all at higher speeds when I’m rapidly accelerating and lifting off the pedal.

Might be how the engine is loaded at higher speeds, etc?

[monster6a2]

Someone forgot their 10mm socket in the engine bay lol

Fr tho it just sounds like something I’d lose.

I’d check for axle play, it’s not engine related that’s fs