Ford Mustang/Capri 1979-1988 Repair Guide



Central Fuel Injection (CFI) is a throttle body injection system in which two fuel injectors are mounted in a common throttle body, spraying fuel down through the throttle valves at the bottom of the body and into the intake manifold.

All 1984-86 models with CFI are equipped with two electric pumps. A low pressure pump is mounted in the tank and a high pressure pump is externally mounted.

Electric fuel pump circuits are equipped with an interlock system which provides power to the pump during start-up, through the starter relay, and provides operating voltage during engine operation. Should the engine lose oil pressure, the pump is automatically disconnected, stopping the engine.

Fuel is supplied from the fuel tank by the combination of a low pressure, in-tank fuel pump and a high pressure, in-line fuel pump. The fuel passes through a filter and is sent to the throttle body where a regulator keeps the fuel delivery pressure at a constant 39 psi. The two fuel injectors are mounted vertically above the throttle plates and are connected in line with the fuel pressure regulator. Excess fuel supplied by the pump, but not needed by the engine, is returned to the fuel tank by a steel fuel return line.

The fuel injection system is linked with and controlled by the Electronic Engine Control (EEC) system.