Fuel Delivery and Air Induction: Description and Operation

The Electronic Fuel Injection (EFI) system is a multi-point, pulse time, speed density fuel injection system, Figs. 1 through 5. Fuel is metered into the air intake stream in accordance with engine demand through injectors mounted on a tuned intake manifold.
An electronic engine control computer (EEC IV) receives signals from various engine sensors and computes the required rate of fuel flow to maintain an optimum air/fuel ratio throughout the entire range of engine operation. The computer then sends a command to the fuel injectors to meter the appropriate quantity of fuel.
The fuel charging manifold assembly houses the injectors which are mounted directly above each of the engine's intake ports. When energized, the injectors spray a metered quantity of fuel into the intake air stream.