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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 1999 🢒 Firefly (Canada) 🢒 Engine 🢒 Engine Controls - 1.3L 🢒 Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Between 10-35 Degrees C (50-95 Degrees F)
Table 1: Example

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

  2. The initial voltage that is displayed by the DMM may be inaccurate because of the initial current surge. Therefore, record the lowest voltage that the DMM displays after the test has run for one second. The voltage that is displayed by the DMM should be within the specified range. Refer to the example. The voltage that is displayed by the DMM may increase throughout the test. The increase may occur when the fuel injector windings warm, and the resistance of the fuel injector windings changes. An erratic voltage reading indicates an intermittent connection within the fuel injector.

Example

Resistance Ohms

Voltage Specification at 10°C to 35°C (50°F to 95°F)

12.0-13.0

5.7-6.6 volts

Fuel Injector Number

Voltage Reading

Pass/Fail

1

6.3

P

2

5.9

P

3

4.8

F

4

6.1

P

Step

Action

Value(s)

Yes

No

1

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

-

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

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

Is the engine coolant temperature within the specified limits?

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

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.

  1. Turn OFF the ignition.
  2. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  3. Disconnect the fuel injector electrical connectors.
  4. Connect the J 39021 power leads of the fuel injector tester to B+ and to ground.
  5. Set the amperage supply selector switch on the fuel injector tester to the Coil Test 0.5 amps.
  6. Connect the leads from the J 39021 DMM to the fuel injector tester. Refer to the illustration associated with the test description.
  7. On the DMM, select the DC voltage and set the DC voltage to the tenths scale (0.0).
  8. Connect the Adjuster Plug Lock Nut fuel injector tester to a fuel injector.

    9. Important:: Check the engine coolant temperature again in order 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. After one second of testing, record the lowest voltage observed.
  12. Repeat steps 8 through 11 for each fuel injector.

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

5.7-6.6V

Go to Step 4

Go to Sequential Multiport Fuel Injector Balance Test

4

Replace any faulty fuel injectors. Refer to Fuel Injector and Fuel Rail Replacement .

Is the action complete?

-

Go to Sequential Multiport Fuel Injector Balance Test

-