Thread: What is this sound!

Originally Posted by Macadamia

sadly not. I secured that one loose heatshield but it hasn't made a difference. I feel like the sound maaaay be coming from around the drive shaft CV joint - I guess to rule it out I will remove that heatshield completely for a breif period and see if it still happens. and will continue to rule out things until I find the cause.

Don't have to remove it, jam rags behind it

It’s hard to make out from the video but does the sound happen when the suspension is pushed up by the bumps in the road - or - does it happen on flat sections..

Originally Posted by HarryO

It’s hard to make out from the video but does the sound happen when the suspension is pushed up by the bumps in the road - or - does it happen on flat sections..

I feel like it happens mostly just coming out of a saddle or when there's a change in incline of the road so to some extent yes when the suspension is pushed up... but its definitely not hitting the bumps. it is such a gentle incline in that video. Its also intermittent - it happened once on a route I drive daily and then never again

As others have mentioned...
I had a customers D4 do this yesterday.
Although all the pressed alloy foil heat shields were in place, I moved them slightly, as in with my hands to change their shape, fix it.

Check the dust shields on the rear brakes for cracking at the bolt holes.

Do you have rear A/C? Mine vibrated like hell as the blower was imbalanced/dirty.

Check that the strip between the front windshield & roof has not come loose. This has vibrated at speed on occasion. I just give it a thump in the middle.

Originally Posted by Graeme

Check the dust shields on the rear brakes for cracking at the bolt holes.

I'll see if I can get to them without removing the wheels, otherwise will check on them next time I rotate.

Originally Posted by imaz

Do you have rear A/C? Mine vibrated like hell as the blower was imbalanced/dirty.

no rear A/C. just the poverty pack for me!

Originally Posted by Pat

Check that the strip between the front windshield & roof has not come loose. This has vibrated at speed on occasion. I just give it a thump in the middle.

It *is* loose (a pressure washing accident) along with the a frame plastic trim which both occasionally vibrate in the wind but what I've capture is definitely not them. The sound is coming from somewhere mid to rear of the underside of the car.

Unfortunately I'm back in lockdown so no long drives to test out after removing the headshield over the drive shaft.