hi
the attached pic shows a small hose connected to the cam cover. The hose was disconnected and i am not sure how or what is connected to it. I was thinking it had check valve so i put it in with the direction of flow away from the cover.
my question:
does anyone have an accurate diagram as how it is connected?

thanks in advance.

 

That hose goes there.... There is no check valve. It goes down to the PCV valve under the intake

 

thanks,, so i can put a straight through connection to it and i should be good to go,

 

I have the same year A4, that hose runs to the PCV valve running off your breather hose under the intake manifold. That hose does have a check valve, depending on the PCV system your engine has. The older 1.8 has a 19mm PCV. The midyear (my version) uses a PCV with 3 ends and a check valve on that hose. The later 1.8 uses a PCV with a built-in check valve and the hose just runs straight from the VC to it.

 

so one with 19mm pcv does not have a check valve if i measure it and it is not 19 then i need a check valve.
if i need a check valve should the flow go to the pcv or to the cam cover?
How do i know if my pcv has a check valve?

 

Check valves will ALWAYS go in the direction of the intake manifold. This prevents boost from leaking back into the system.