Size of vacuum hose for fuel regulator to intake manifold?

[Itsme]

Originally Posted by Luka

Just replaced intake manifold gaskets and noticed this vacuum line is not in great condition and needs replacing. Does anyone know what size it is? thanks

Take it off and go to any auto shop, they will give you the correct size and length required.

[oldel]

Always bet on 3mm.
If it ends up being 4 or 5 mm then there's a chance the 3mm could still be forced on with hot water or heat gun. Vice versa no good and will leak

Seriously though, that looks old, looks like 5 mm.