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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 1999 🢒 Grand Prix 🢒 Engine 🢒 Engine Controls - 3.1L 🢒 Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Between 10-35 Degrees C (50-95 Degrees F)
Table 1: Example
Table 2: Fuel Injector Coil Test - ECT within 10-35°C (50-95°F)

Object Number: 17707 Size: MF

Test Description

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.

  1. The engine coolant temperature affects the ability of the fuel injector tester to detect a faulty fuel injector. If the engine coolant temperature is NOT between 10°C and 35°C (50°F and 95°F), go to Fuel Injector Coil Test Procedure - Engine Coolant Temperature Less Than 10°C (50°F) or Greater Than 35°C (95°F).

    2.

  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 (large fluctuations in voltage that do not stabilize) indicates an intermittent connection within the fuel injector.

Example

Resistance Ohms

Voltage Specification at 10°C-35°C

(50°F-95°F)

11.4-12.6

5.7-6.6

Fuel Injector Number

Voltage Reading

Pass/Fail

1

6.3

P

2

5.9

P

3

6.2

P

4

6.1

P

5

4.8

F

6

6.0

P

Fuel Injector Coil Test - ECT within 10-35°C (50-95°F)

Step

Action

Value(s)

Yes

No

1

Did you preform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

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

Does the engine coolant temperature measure within the specified limits?

10°C-35°C (50°F-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 OFFthe ignition.

    2. 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. Access the Fuel Injector 10 way electrical connector and install the J 39021 using J 39021 - 210 Injector Selector Switch Box, and J 39021 - 306 Fuel Injector Test Harness.

    4. Important: The Injector Selector Switch Box, and Fuel Injector Test Harness should be used inorder to prevent from removing the upper intake manifold to preform the injector balance test.

  4. Connect the J 39021 fuel injector tester to B+ and ground.
  5. Set the amperage supply selector switch on the fuel injector tester to the Coil Test 0.5 amp position.
  6. Connect the leads from the J 39200 Digital Multi Meter (DMM) to the fuel injector tester.
  7. Set the DMM to the tenths scale (0.0).
  8. Select a injector using J 39021 - 210 injector selector switch box.

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

  10. Observe the voltage reading on the DMM.
  11. Record the lowest voltage observed after the first second of the test.
  12. Repeat Steps 8 through 11 for each fuel injector.

Did any fuel injector have an erratic voltage reading (large fluctuations in voltage that do not stabilize) or a voltage reading outside of the specified limits?

5.7-6.6  volts

Go to Step 4

Go to Fuel Injector Balance Test

4

Remove the upper intake manifold Refer to Intake Manifold Removal (Upper VIN M) .

Did you complete the removal?

--

Go to Step 5

--

5

Inspect fuel injector electrical harness for connector terminal damage, shorts, opens,and grounds. Refer to Wiring Repairs and Repairing Connector Terminals .

Did you find and repair the condition?

--

Go to Fuel Injector Balance Test

Go to Step 6

6

Replace the faulty fuel injectors.

Refer to Fuel Injector Replacement

Is action complete?

--

Go to Fuel Injector Balance Test

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