The numbers below refer to the step numbers in the diagnostic procedures.

4

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.

5

The fuel pressure should be within the specified range. If the fuel pressure is not within the specified range, see FUEL SYSTEM DIAGNOSIS in appropriate BASIC DIAGNOSTIC PROCEDURES article.

6

The fuel pressure should reach a steady value. If the fuel pressure does not reach a steady value, see FUEL SYSTEM DIAGNOSIS in appropriate BASIC DIAGNOSTIC PROCEDURES article.

7

The fuel injectors are flowing properly if the pressure drop value for each fuel injector is within 1.5 psi of the average pressure drop value. Calculate the pressure drop value for each fuel injector by subtracting the second pressure reading from the first pressure reading. Refer to Fuel Injector Balance Example. See FUEL INJECTOR BALANCE EXAMPLE table.

FUEL INJECTOR BALANCE EXAMPLE

Cylinder No.	First Reading	Second Reading	Amount Of Drop	Average Range: 35-38 psi
1	47 psi	36 psi	11 psi	Good
2	47 psi	34 psi	13 psi	Faulty, Too Much Drop
3	47 psi	37 psi	10 psi	Good
4	47 psi	39 psi	8 psi	Faulty, Too Little Drop

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Fuel Injector Balance Test: Description