What's the name of the hose on the intake manifold?

The hose on the intake manifold is called the vacuum tube of the oil pressure regulator.

The hose has three functions: first, it allows the rigid pipes at both ends of the hose to have slight relative displacement, which is a better way to deal with vibration and a means to compensate thermal deformation; The second is to find the manufacturing error, so that the two rigid pipes that need to be butted don't have to be aligned very accurately, so it is not necessary to improve the manufacturing accuracy and increase the manufacturing cost. The use of the hose on the intake manifold takes these two functions into account; Third, it is omnipotent, as long as it can be reached and the length is enough, and there is no need to consider the curved shape.

For carburetor or throttle body gasoline injection engine, intake manifold refers to the intake pipe from the back of carburetor or throttle body to the front of cylinder head intake. Its function is to distribute the mixture from carburetor or throttle body to the air intake of each cylinder.