Was tired last night when I posted this thread so might not have explained the issue clearly.
The metco breather comes with the one way check value. It’s now missing.
Without the one way value, Could this lead to loss in vacuum pressure in the engine?
Basically, there is on cap on the value cover.
Btw, my cat has turn downs for exhaust and the reason I could not test the factory value cap last night. Neighbors hate this car enough...didn’t want to crank up the beast at 10:00pm. LOL 😂🤣😎