Fuel Delivery and Air Induction: Description and Operation
Electronic Fuel Injection:
The Sequential Electronic Fuel Injection (SEFI) system is a multi-point, pulse time, speed density fuel injection system. Fuel is metered into each intake port in sequence with the engine firing order in accordance with engine demand through the injectors mounted on a tuned intake manifold. California vehicles use a Mass Air Flow Sensor to provide additional information to the ECA.
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 EEC-IV engine control system determines and compensates for changes in altitude (i.e. from sea level to mountains). The system will also automatically compensate for the age of the vehicle and its uniqueness. For manual transmission vehicles it will also permit for push-starting if it becomes necessary.
The fuel delivery system consists of a high pressure in-tank mounted electric fuel pump, fuel supply manifold, pressure regulator, fuel injectors, fuel filter/reservoir, inertia switch, fuel tank and connecting lines.