Road noise - please help!

[tomlinp76]

Hi all.

I am really hoping some in the community can help try to diagnose a really strange increase in road noise that I’m getting, shortly after having a replacement heater box fitted in my A3 convertible (a major dash-out job!)

Describing it is difficult but I’ll try. Not as deep as normal tyre noise, not as high as a whistle from wing mirrors. Somewhere in between and it’s a wind-like hum sound.

It’s just noticeable at around 15mph, nicely audible over 30, and doesn’t change pitch with speed - and although always present it will be far worse on rough/concrete roads and much quieter on smooth tarmac especially at higher speeds.

It only comes from drivers side somewhere - I have sat in the passenger seat on Audi test drives and I can’t hear a thing, yet it’s so audible on the drivers side (and as you guessed Audi can’t hear a thing).

Causes? I’ve been concerned it was work associated with the heater box but it’s been checked, is properly sealed and in any case does not extend towards the drivers side.

Tyres are relatively cheap Barum 235/35/19s and sawtoothed to an extent, but thought most tyre noise was in the lower range.

It’s not wind noise coming into the cabin as even at 70 it can be relatively quiet.

I’m sure the clue is with the tyres due to the road surface variations, but why it’s started happening, and why it’s so high pitched is a mystery - maybe the brand doesn’t suit the car and they’re wearing unevenly more each day. And also how it’s getting in to the cabin - via the wheel well perhaps?

Thanks for any suggestions you may have - my first course of action would be to change tyres, but there’s 6mm still on them so pretty reluctant to.

(I’m considering getting another opinion from an independent specialist -Audi are already aware there’s been £1,500 worth of warranty work on the car already, and a probably sick of seeing it!)

 

[PanamaS3]

what else did they remove and put back other than the heater box?...seems likely related to work Audi did rather than your tyres suddenly becoming noisy....also if noise is coming through a gap in the insulation (caused by Audi not putting things back right) then of course you will hear different road noises as you go over different surfaces.....it must be doing this due to the repairs they did so I'd take it back to them whether they are sick of seeing it or not and insist they fix it

 

[Fatbloke]

The Skoda Octavia (and golfs afaik) had an issue with the rear tyres sawtoothing and causing a drone that sounded like a faulty wheel bearing. Could it be the sawtoothing you mention?

On the VRS, if it happened you swapped front to rear and the tyres started to wear better on the front. Skoda brought out new alignment settings and seems to be ok now.

 

[tomlinp76]

Hi, sorry it's been a while to get back on the forum, but thanks for the posts above.

I have written off to the dealer again outlining my concerns about whether the initial heater box work was at fault. However I'm not really sure it's down to the work they've done - the noise (think blowing over a bottle but an octave higher) tends to come from right in front of me, however tilt head slightly to the side and it's there to a much lesser extent from the rear. Put the roof down, the same noise then appears to come more from the passenger side and behind me.

So you can see the issue, with the roof down it appears it's definitely an outside noise coming in - but when I initially picked the car up it was pretty silent, even with the roof down - definitely didn't have this issue. My best guess is that it's uneven wear on cheap 19 inch low profile tyres - I checked them last night and they're noticeably sawtoothed/cupped on the passenger side outer, and the drivers side inner.

Only time will tell I suppose - I'm waiting for a response from the dealership for a start, then maybe I'd look at replacing the fronts.

Thanks.