Fuel Injector Balance Test With Tech 2

CIRCUIT DESCRIPTION
The scan tool first energizes the fuel pump and then the injectors 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 injector.

TEST DESCRIPTION

Steps 1-5:

Steps 6-8:

The numbers below refer to the step numbers on the diagnostic table.
3. The engine coolant temperature (ECT) must be below the operating temperature in order to avoid irregular fuel pressure readings due to hot soak fuel boiling.
4. 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. 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
6. 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.