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Fuel Injector Balance Test

Schematic:




Injector Balance Test Example (Typical):




Diagnostic Chart (Part 1 Of 2):




Diagnostic Chart (Part 2 Of 2):




TEST DESCRIPTION
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.
6. The fuel pressure should reach a steady value.
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 illustration above.