Gurgling EGR valve
 

On my 3.0 engine I have an odd noise. I have watched several videos on engine vacuum. Several videos show excessive intake vacume . I don’t have that.
When I remove the oil fill cap, the engine stumbles a bit. The vacuum seems about the same as my E39 2.5 engine. My problem is that I am getting a gurgling sound coming through the EGR. ITS resonating through the Pierburg air pump. (Replaced a few years ago.) It is rattling gurgling noise at the the air pump air filter. I removed the EGR. ABSOLUTELY clean as a whistle in there.
I know there is something wrong but I don’t know what. The air oil separator has been replaced prior to my ownership. I think something wrong, but not sure what. I do not have any dash lights or pending codes. Any ideas?

On a side note, I was getting several random bank one or bank lean codes. I really checked over the engine for vacuum leaks.it is a tight engine. I put my scanner and read the live data. I was getting a reading that one or both of my downstream Oxygen sensors was not reporting well. Yet no codes were thrown. A couple of new Bosch sensors fixed that problem right up.