See Figure 1
The Model 400 Electronic Fuel Injection (EFI) system is a computer controlled system that uses a pair of Throttle Body Injection (TBI) units, which are mounted on a single manifold cover on the 5.0L (VIN 7) engine. Since each TBI feeds the cylinders on the opposite side of the engine, the system has acquired the name of Crossfire Injection.
Fuel is supplied, by an electric fuel pump located in the fuel tank, to the front TBI fuel accumulator. From the accumulator, it is carried to the rear TBI fuel pressure regulator by a connecting tube. Unused fuel is sent to the fuel tank through a separate return line.
Fuel is supplied to the engine through electronically pulsed injector valves located in the throttle body.