What is this part called and it's function?
I have a 2011 Audi A7 C7 3.0 TSFI Quattro Right hand drive.
Please see these photos. I'm wondering what the little caps are circled in blue? I am missing the inner two. Should they have caps like the outer two and what function do they serve? Are they sensors of some sort? Where could I get replacement caps?
Thanks in advance,
Alfie
PS nevermind how dirty the car is. It's going for a detail soon!



