Clattering over 50mph

[black_a3]

Hi!

Looking for suggestions on a new noise my A3 is making.

Each time the car goes over 50mph, there is a striking rattling noise that sounds like something is knocking. Hard to say specifically where it comes from, but definitely the front of the car. It gets progressively worse as you go above 50mph, but below 50mph isn't present at all.

I've revved the car up to 5k rpm at lower speeds and it doesn't make the noise, so does seem to be road speed related rather than engine speed.

Car is a 2017 Audi A3 1.4tfsi 150 saloon, on 76,000. I've owned since 2020 and never heard the noise until today.

Any suggestions appreciated.

 

[steverobertsbbc]

So what you're actually probably looking at is an issue that's airspeed related - ie there's enough air pressure once you get above 50 for whatever it is to start rattling. I'd start by checking that all the clips are in place in the underbody covers and also take the front wheels off and check if the thin steel dustcovers behind the brakes have rusted through their mounting points.

 

[JohnM100]

^ This would be the first thing I would check also.

 

[AlS3BE]

Sounds similar to noise I had when a few of the screws in the undertray mysteriously went missing after a service.