My engine code is ALT. Which seems to be not very common.
There is some sort of a valve on the valve cover, which I believe to be a vacuum activated breather valve or something. It's removed in the photo.
Here is the thing itself: (06B 103 235E)
I can't find any info on this. What I do know is that mine is full of oily gunk and is clearly broken inside. If it wasn't broken before, it is broken now because I was messing with it. 
Anyway it has four ports, one to the valve cover, one to the air intake (after the MAF) one to a plastic bottle which I thing is a vacuum reservoir, and one to the vacuum source ( circled in this photo which I think is a suction pump but again I can find no info on this exact part, 06B 133 753C
Also, the pipe between this valve thingy and the suction pump is full of oily crud.
The connections to the air intake and the vacuum bottle are both sheared off.
So, what got me looking at this area is a DTC I keep getting. I have 2 scanners(both cheapies)
Scanner 1 is giving me 17544 - Long Term Fuel Trim Add.Fuel,Bank1 System too Lean
Scanner 2 is giving me P0171 - Fuel Trim,Bank1 System too Lean
I erased the code on Saturday morning, but prior to that, I noticed the Long Term FT was zero, indicating the car was operating in Open Loop. I checked the LTFT yesterday and it was -12.5
The MAF looks OK, reading about 2.5-4 g/s in idle, depending on engine temp.
I would appreciate any input on what these bits are/do and if I'm on the right track regarding the DTC above.