What is a plenum gasket?

The plenum gasket is a paper or rubber that creates a seal between the upper intake manifold and lower intake manifold. The plenum gasket is also known as the intake manifold gasket or caterpillar gasket.

When pulling out the intake manifold, this gasket is almost always damaged. It is externally fragile and practically impossible to reuse without creating a vacuum leak. Since removing the intake manifold is expensive and time-consuming, it is highly recommended that the plenum gasket be replaced every time the intake manifold is removed. The intake manifold is a part of the engine that supplies a precise mixture of air and fuel to the cylinders.