Operation CHARM: Car repair manuals for everyone.

General System Description

PURPOSE
The purpose of the fuel supply system is to provide the fuel metering system with a constant supply of high pressure fuel.

OPERATION
The fuel supply is stored in the fuel tank. An electrical fuel pump contained in the modular fuel sender assembly pumps fuel through an in-line fuel filter to the fuel rail assembly. The pump is designed to provide fuel at a pressure above the regulated pressure needed by the injectors.

Fuel is recirculated through the fuel rail continuously while the engine is running. This removes air and vapors from the fuel as well as keeping the fuel cool during hot weather operations.

The fuel pressure regulator that is mounted on the fuel rail, maintains a variable pressure across the injectors based on intake manifold vacuum (load). It is accomplished by controlling the amount of fuel that is recirculated back to the fuel tank.

Unleaded fuel must be used with all gasoline engines for proper emission control system operation. Using unleaded fuel will also decrease spark fouling and extend engine oil life. Leaded fuel can damage the emission control system, and its use can result in loss of emission warranty coverage.

All vehicles with gasoline engines are equipped with an Evaporative Emission System that minimizes the escape of fuel vapors to the atmosphere.