Please help... what is this part circled?

[_G_]

I've been trying to figure this out for a while now... mine has an additional hose connected to it which is covered in oil... I traced this hose across the engine (underside of the high pressure fuel rail, attached with plastic ties)... down the cam shaft side side... and to the bottom of the driver side bulk head... that's as far as I've got...

This valve type thingy that is connected to the manifold is fed by the pcv... so I'm guessing it is all pcv related... as these engines have excess crankcase pressures and not the best escape routes...

It loos like an OEM part... anyhow... 2.0 TFSI (BWA)

I screwed the hose back on tight... but oil is still finding its way out through the threading and the plastic tie securing the hose to this valve is useless.

 

[_G_]

The hose running along the side the fuel rail... (red arrow pointing left) tied to it with plastic ties:

thank you

 

[OCD-A3]

The connection from the intake manifold to the valve cover is indeed for the PCV. The hose you described that runs along the fuel rail and down the side of the engine sounds like it could be a vacuum line for a boost gauge, although I'm not 100% sure as I have the older FSI motor. Perhaps it's something that the previous owner had installed?

 

[Silky-S3]

Boost tap for gauge. Thats how I've run mine as well

 

[_G_]

I don't have a boost gauge though...

its leaking from the hose that connects to this thread... i unscrewed the hose and some oil came out... i squeezed the hose gently and connected it back on but the threading inside the hose seems dead... (not cross threaded) but when I tightened it kept turning so something is spinning inside the hose... yeh and after squeezing the hose... the car ran like a dream! hasnt run like that in a long time... it was so responsive like a couple of psi were back but no fault codes on vcds.

can i block the connection off and stick the hose onto a catch can?

cheers for the replies