For 1990-2009 cars

### Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. The engine coolant temperature (ECT) affects the ability of the fuel injector tester to detect a faulty fuel injector. Therefore the test results are only valid when the engine coolant temperature is between 10-35°C (50-95°F).

2. The first second of the voltage displayed by the DMM may be inaccurate due to the initial current surge, therefore, record the lowest voltage displayed by the DMM after the first second of the test. The voltage displayed by the DMM should be within the specified range. Refer to the Example. The voltage displayed by the DMM may increase throughout the test as the fuel injector windings warm and 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.

Ohms | Voltage Specification at 10°C-35°C (50°F-95°F)
--- | ---
13.4-14.4 | 6.7-7.7 V
Fuel Injector Number | Voltage Reading | Pass/Fail
1 | 7.3 | P
2 | 7.0 | P
3 | 6.2 | F
4 | 7.1 | P

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | Go to Diagnostic System Check - Engine Controls
2 |

1. Connect the scan tool.
2. Check the engine coolant temperature.

Is the engine coolant temperature within the specified range?

10-35°C (50-95°F)

Go to Step 3

Go to Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Outside 10-35 Degrees C (50-95 Degrees F)

3 |

1. Turn OFF the ignition.

Caution: Wrap a shop towel around the fuel pressure connection in order to reduce the risk of fire and personal injury. The towel will absorb any fuel leakage that occurs during the connection of the fuel pressure gage. Place the towel in an approved container when the connection of the fuel pressure gage is complete.

Notice: In order to prevent flooding of a single cylinder and possible engine damage, relieve the fuel pressure before performing the fuel injector coil test procedure.

2. Relieve the fuel pressure. Refer to Fuel Pressure Relief .
3. Connect the J 39021 Fuel Injector Tester to B+ and ground.
4. Set the amperage supply selector switch on the fuel injector tester to the Coil Test 0.5 amp position.
5. Connect the leads from a DMM to the fuel injector tester. Refer to the illustration associated with the test description.
6. Set the DMM to the tenths scale (0.0).
7. Disconnect the fuel injector electrical connector.
8. Use 2 jumper wires from the J 35616 Connector Test Adapter Kit in order to connect the fuel injector to the J 39021 leads.

Important:: Check the engine coolant temperature again to ensure that the correct chart is being used.

9. Press the Push to Start Test button on the fuel injector tester.
10. Observe the voltage reading on the DMM.

Important:: The voltage reading may rise during the test.

11. Record the lowest voltage observed after the first second of the test.
12. Repeat step 7 through step 11 for each fuel injector.

Did any fuel injector have an erratic voltage reading or a voltage reading outside of the specified range?

6.7-7.7 V

Go to Step 4

Go to Fuel Injector Balance Test with Special Tool

4 | Replace the faulty fuel injectors. Refer to Fuel Injector Replacement . Is the replacement complete? | -- | Go to Fuel Injector Balance Test with Special Tool | --