I'm trying to eliminate cutting out issues. New sensor kit being fitted. Found this breather valve on the plenum. Is it required or not - and where would the hose normally go? I see some being removed and blanked off.
Tried the compressor on it and air seems to get in but not out.
Cheers.

 

Part of original breather system. Nope you don't need it. Remove and blank. I believe hose would have gone to the flame trap...

 

Thanks.

 

I think it’s a non return valve so should only work one way! Someone correct me if I’m wrong?

 

Correct its a non return valve.