Fuel Injector Balance Test with Tech 2

FUEL INJECTOR BALANCE TEST WITH TECH 2

CIRCUIT DESCRIPTION
The scan tool first energizes the following components for a precise amount of time allowing a measured amount of fuel into the manifold:
- High pressure lock off (HPL)
- Low pressure lock off (LPL)
- CNG fuel injectors

This causes a drop in system fuel pressure that can be recorded and used to compare each fuel injector.

TEST DESCRIPTION

Step 1 - Step 5:

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
4. The fuel pressure should reach a steady value. Refer to Fuel System Diagnosis if the fuel pressure does not stabilize. 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.