Table 1: | Example |
Table 2: | Engine Coolant Temperature Outside 10°C - 35°C (50°F - 95°F) Test Procedure |
Highest Voltage Reading | Acceptable Subtracted Value Above/Below 10°C-35°C (50°F-95°F) | ||
---|---|---|---|
7.1 Volts | 0.6 Volts | ||
Injector Number | Voltage | Subtracted Value | Pass/Fail |
1 | 9.8 | F | |
2 | 6.6 | 0.5 | P |
3 | 6.9 | 0.2 | P |
4 | 5.8 | 1.3 | F |
5 | 7.0 | 0.1 | P |
6 | 7.1 | 0.0 | P |
The numbers below refer to the step numbers on the diagnostic table:
The engine coolant temperature (ECT) affects the ability of the fuel injector tester to detect a faulty fuel injector. If the ECT is NOT outside the range of 10°C-35°C (50°F-95°F), go to Fuel Injector Coil Test Procedure--Engine Coolant Temperature Between 10°C-35°C (50°F-95°F).
During the first second, the voltage that is displayed by the DMM may be inaccurate due to the initial current surge. Record the lowest voltage that the DMM displays after the first second of the test. The voltage that the DMM displays may increase throughout the test when the fuel injector windings warm, and when the resistance of the fuel injector windings changes. An erratic voltage reading, or large fluctuations in voltage that do not stabilize, indicates an intermittent connection within the fuel injector. From the recorded voltages, identify the highest voltage, excluding any voltages that are more than 9.5 volts. Subtract each voltage that is less than 9.5 volts from the highest voltage. Record each subtracted value. Refer to the example below. The subtracted value for any fuel injector must not exceed 0.6 volt. A fuel injector with a subtracted value that is more than 0.7 volt is considered faulty, and must be replaced. A fuel injector with a recorded voltage that is more than 9.5 volts is also considered faulty, and must be replaced.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
2 2 |
Is the temperature outside the specified value? | 10°C-35°C (50°F-95°F) | ||
3 3 |
Important: The fuel system must not be pressurized.
Does any fuel injector have an erratic reading, or have a reading that is more than the specified value? | 9.5 Volts | ||
4 |
Does any subtracted value exceed the specified value? | 0.6 Volts | ||
5 | Replace the faulty fuel injectors. Refer to Fuel Injector Replacement . Did you complete the replacement | -- | -- | |
6 | Does any driveability condition still exist? | -- | Go to Applicable Diagnostic | System OK |