Fuel Injector Balance Test

Fuel Injector Balance Test (1 Of 2):

Fuel Injector Balance Test (2 Of 2):

Fuel Injector Balance Test:

Fuel Injector Balance Test:

Circuit Description
Use the Fuel Injector Tester (J 39201) in order to energize the injector for a precise amount of time, thus allowing a measured amount of fuel into the manifold. This causes a drop in the fuel rail pressure that can be recorded and used to compare to each injector. All injectors should have the same pressure drop ±1O kPa (1.5 psi).

Test Description
The numbers below refer to the step numbers in the diagnostic table.

WARNING: Relieve the fuel system pressure before servicing fuel system components In order to reduce the risk of fire and personal injury, after relieving the system pressure, a small amount of fuel may be released when servicing the fuel lines or connections. In order to reduce the chance of personal Injury, cover the regulator and the fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out. Place the towel In an approved container when the disconnection Is complete.

4. The engine coolant temperature must be below the operating temperature in order to avoid irregular fuel pressure readings due to Hot Soak (fuel boiling).
5. The fuel pressure should be within the specified range. If the fuel pressure is not within the specified range, refer to Fuel System Pressure Test. System Diagnosis - Fuel System Pressure Test
6. The fuel pressure should reach a steady value. If the fuel pressure does not reach a steady value, refer to Fuel System Pressure Test.
7. If the pressure drop value for each fuel injector is within 10 kPa (1.5 psi) of the average pressure drop value, the fuel injectors are flowing properly. Calculate the pressure drop value for each fuel injector by subtracting the second pressure reading from the first pressure reading. Refer to the figure.