Having just been to Audi to collect my new MAF, I notice something I've never spotted before. The circled pipe looks unusual; I'm sure it had a black screw cover on?! What is this pipe? Am I OKAY to run the car for now without the 'so called' cover? (it is located at the rear of the bay as you can see, on the right hand side, behind the TIP (intake pipe)) Any help much appreciated.. Thank you.