Hello, Can someone please give me a hint to what this sound might be? (please forgive the idiot Lumia 950 wobbly camera...) The car is an Audi A4 Avant 2.0 TDI, 2005 July. The engine is an BLB. I bought the car in January this year with only 118000 km because it belonged to a person with disabilities. Of course I'm always thinking at the dreaded oil pump failure, I did the so called "dip test" but who can tell for sure?... But this sound is only present when the engine is cold and idle. From what I can tell, it doesn't sound like the oil pump chain or stuff related to that (info on this page here http://bit.ly/2szbnTG). I've asked some people but they don't know. I would really appreciate the help. Regards, Emanuel R.