Mick in Kerry

Refer to the prev post from Just Rob. Just replaced the plastic flange on mine.

I found the same issue under my 05 A4 avant quattro tfsi. Nearly fell over when I saw the extent of the rust above the rear spring supports (hidden under the felt wheel-arch cowling) and bad rust all along under sills from rear to front hidden above the plastic undertrays. NCT in Ireland is pretty thorough but none of this rust was spotted so the car flies through every year. The rust stops where the plastic undertray stops i.e. where the chassis is permanently exposed and can dry out properly. I'm getting the car welded. Plastic undertrays/felt cowlings free to take away - belly will remain naked from now on!