Protege L4-1839cc 1.8L DOHC (1990)
Air Filter Element: Description and Operation
Intake Air System
Dirt and dust particles in the air are abrasive and, if allowed to enter the engine with the intake air, can cause significant damage in a relatively short
period of time. The air cleaner assembly contains a paper filter element that removes these particles from the intake air.
Two resonance chambers are connected to the intake air ducts. One chamber, called the resonance duct, is a silencer connected ahead of the air cleaner
to reduce intake noise. The other, simply called the resonance chamber, helps take advantage of harmonic oscillations within the intake system to
improve volumetric efficiency at low engine speeds, and increase low speed torque.
Other intake system components include the throttle body, bypass air control valve, and air ducts. These components are listed separately in this section.
