The small circular retaining bracket that fits over the plastic Y pipe is lost on my coolant expansion tank return line. Part # C2Z14540

Does anyone know if this grey Y connector is actually functional? The barbed fitting does not go to anything.

If it is not, is there any reason that I cannot run a standard hose I'm place of this? From throttle body to expansion tank, or a barb to eliminate this plastic (grey) y connection.

a commenter on FB said it's a one way valve. I can't think what possibly for. Bleed air? Test pressure in the system? Doesn't seem big enough. I'd prefer to eliminate all together if it doesn't serve a purpose.

This ironically could be the source of my coolant leak.

 

I have no idea what it does, but I do know you're supposed to have a clip holding black hose end into the grey (seemingly pointless) Y connector - the clip is identical to the one that holds the thin pipe that goes to from the coolant expansion tank to the front crossover pipe above the throttle body. It slides in the grooves on the black pipe and around the "collar" of the Y piece it goes into. Looks like you're missing it here, that could well contribute to a leak..

 

I realized that as well when putting the car back together. Someone in the Facebook group said its part of the self breathing system, but this is the only type valve in the entire coolant system I have seen. As it also goes to the expansion tank I see little function in this part.

Would be great to hear from someone who's cut it open and knows what the internals look like.