Hi all, 
I have an Audi A4 B8 Diesel S Line TDI
We are trying to remove the air box housing, there is a cable running through the bottom of it which we can't work out what it is, it does look as though it controls a valve of some sort. Does anyone know, if we were to upgrade the box would we need to cut this cable or how we'd remove it?
Thanks,

Welcome to the forum Amelia, you'll find the members on here are a friendly and helpful bunch 🙂 

Could the cable be linked to the maf sensor? If Have you got any pics? 

To remove the airbox start removing the wire over the top of it. then remove screws. look for two or three connecting the tubing then pull the tubing out. once all screw are gone pull the box straight up and it will pop out with those rivets.

Here's a couple of YouTube videos which might help: 

Cheers

Steve