green hose valve cap (identify this part?)

hi everyone, what is that green hose valve cap, mine come without the valve, direct hose.

Attachment 5400

thanks

Attachment 5401
This is the tag beside the green valve cover. My guess is emissions related as it's attached to
The intake manifold. Possibly fuel tank evaporation collection/canister hose back to the engine?

thanks, is not EGR valve related then, is to make a evap valve service, cleaning maybe

was thinking it would be interesting to make a EGR hose stopcock looking like that green cap

Evaporator service port: for servicing the air conditioning system

[evap=evaporative emission controls?..looks like low pressure pipe into cam cover??

pressurize to check for leaks??

1 psi u really think thats ac?..

It is used to hook up a smoke machine to find a leak if there is a leak.

Thats right its for leak detection in evap system which must be used with diag tool to open and close evap valves while testing.