What is the purpose of the firewall in a vehicle?

The firewall in a vehicle serves as a crucial safety feature that separates the engine compartment from the passenger compartment. Its primary purpose is to provide a barrier that protects occupants from the heat, noise, and potential hazards coming from the engine. This can be vital in the event of a fire in the engine compartment, as the firewall helps to limit the spread of flames and smoke into the area where people are seated. Additionally, it helps to insulate the cabin from engine noise and vibrations, contributing to overall comfort during travel.

The other options do not accurately describe the function of the firewall in a vehicle. Enhancing audio quality pertains to components related to sound systems rather than structural features. Supporting the vehicle chassis is more aligned with the role of the frame and suspension system. Acting as an air filter is a function associated with the air intake system rather than a structural component designed for safety and separation.