Measurement of pressure in the fuel injection system

Four cylinder engine (except 1991 models)

1. The CFI fuel injection unit is equipped with either fork tips (used in earlier models) or spring-loaded connectors (used on later CFI models). In any case, you will need an adapter to install a pressure sensor between the fuel supply line and the injection unit (see picture).



2. Relieve pressure in the fuel system (see section 2).

3. Disconnect the fork connector or spring lock connector and separate the supply line (he is more) from the charging station (see section 3).

4. Through the adapter, install the pressure sensor between the disconnected fuel supply pipe and the injection unit pipe.

5. Turn on the inertial switch (see section 2).

6. Start the engine, check the fuel pressure in the system at idle and compare with the value specified in the specification. Increase RPM, pressure should be constant regardless of engine RPM.

7. If the indicator shows a pressure value above the allowable value, then either the pressure regulator is clogged (see section 11), or the fuel return line is clogged.

8. If the pressure value is below the permissible value, then the fuel pump is faulty (see section 4), the injector is leaking (see section 12), the fuel suppression line is blocked, or there are leaks somewhere in the fuel supply or return lines (see section 3).


9. Depressurize the fuel system again, remove the sensor, connect the supply pipeline to the fuel recharging unit.

10. Turn on the inertia switch, start the engine, check for leaks.

1991 four-cylinder engines and all V6 engines

11. Easily and quickly you can measure the fuel pressure in the system. using a Ford pressure sensor T80L - 9974 - B (or similar) and adapter T85L - 9974 - A (or equivalent). V6 engines with CFI systems are equipped with Schrader valves. therefore, it is not necessary to disconnect the fuel lines to take readings from the sensors.

12. Ford Fuel Pressure Relief/Measurement Kit consists of sensor assembly and adapter complete with Schrader valve. If you have such a sensor, you can use this method as an alternative to the one described in section 2.

Warning: Do not attempt to relieve pressure through the Schrader valve without a special tool.

13. To connect the sensor, simply remove the valve cap. screw on the adapter, then connect the sensor to the adapter.

14. Start the engine and let a constant idle speed be established. Note the fuel pressure value and compare it with the specification.

15. If the pressure value is lower than those given in the specification, it is possible that the fuel line is leaking, the pump is faulty, or there is a leak in the nozzle.

16. When pressure values are higher than normal, the cause may be a blockage in the fuel line or fuel pressure regulator. See the relevant section on the fuel injection system.