Fuel Pump: Description and Operation

Fig. 7 Fuel pump wiring diagram. 1985 - 87 4-140 EFI except Aerostar & V8-302, Early 1986 Aerostar 4-140 EFI, 1986-87 V6-177 & 1987 6-300 models w/single fuel tanks:

Fig. 8 Fuel pump wiring diagram. 1985-87 4-140 EFI & V8-302, 1986-87 V6-177 & 1987 6-300 w/dual tanks:

High Pressure Pump:

Fig. 11 Fuel pump wiring diagram. 1986 - 87 V6-183 & Late 1986 & 1987 Aerostar 4-140 EFI:

GASOLINE ENGINES EXCEPT V8-460

On vehicles with single fuel tanks, the electrical system, Figs. 7, 8 and 11, provides power to both the fuel pump relay and a timing device in the EEC module. On vehicles with dual fuel tanks, the electrical system, Fig. 9, has a fuel pump relay, controlled by the EEC module, which provides power to the fuel pump under various operating conditions.