Fuel Injector Balance Test With Special Tool

FUEL INJECTOR BALANCE TEST WITH SPECIAL TOOL

CIRCUIT DESCRIPTION
The J 39021 Fuel Injector Tester energizes the CNG fuel injector for a precise amount of time allowing a measured amount of fuel into the manifold. This causes a drop in system fuel pressure that can be recorded and used to compare each fuel injector.

TEST DESCRIPTION

Step 1 - Step 6:

Step 7:

The numbers below refer to the step numbers on the diagnostic table.
3. The fuel pressure should be within the specified range. Refer to Fuel System Diagnosis if the fuel pressure is not within the specified range. Component Tests and General Diagnostics
5. If the pressure drop value for each fuel injector is within 14 kPa (2.0 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.