The engines covered by this information employ a Multi-Port Fuel Injection (MFI) system. The MFI system injects fuel into the intake manifold above the intake valve port of each cylinder through separate injectors.
The fuel system consists of the fuel tank, electric fuel pump, fuel filter, fuel tubes, fuel hoses, vacuum hoses, throttle body, and the fuel injectors.
A fuel return system is used on all vehicles. The system consists of the fuel tubes and hoses that route fuel back to the fuel tank.
The fuel tank assembly consists of the tank, filler vent tube, a fuel gauge sending unit/fuel pump assembly, and a pressure filler cap (on some models).
Another part of the fuel system is the evaporation control system, which is designed to reduce the emission of fuel vapors into the atmosphere. The description and function of the evaporative control system is found in Driveability & Emissions Controls .
PREMIER AND MONACO
The Premier and Monaco vehicles are available with two different ignition, fuel, and emission systems. The system change came in mid-1991. 1988-90 and early 1991 vehicles will be referred to as "early Premier and Monaco''. The late 1991 and all 1992 models will be referred to as "late Premier and Monaco''. Early and late vehicles are distinguishable from each other by the shape and position of the ignition coil, air cleaner, and relay box, as well as other engine compartment components.
Early vehicles use:
Late models use: