What component maintains fuel pressure in a pressure-injection carburetor?

In a pressure-injection carburetor system, the engine-driven fuel pump is the component responsible for maintaining fuel pressure. This type of carburetor requires a consistent and adequate fuel supply to ensure that the fuel is atomized and mixed properly with air for combustion. The engine-driven fuel pump operates directly off the engine, providing the necessary pressure to push fuel through the system and into the carburetor. It is designed to respond to the engine's demands, adjusting the fuel flow as necessary based on engine speed and load.

Other systems such as electric fuel pumps can provide fuel delivery, but they are typically found in fuel-injection systems rather than pressure-injection carburetors. Meanwhile, a gravity feed system relies on the physical force of gravity to deliver fuel, which may not provide consistent pressure under varying conditions. Manual fuel control mechanisms allow for the adjustment of fuel flow but do not actively maintain fuel pressure in the same continuous manner as an engine-driven fuel pump. Therefore, the engine-driven fuel pump is essential for ensuring the optimal performance of a pressure-injection carburetor by maintaining the required fuel pressure.