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For 1990-2009 cars only
Makes 🢒 Buick 🢒 2005 🢒 LaCrosse 🢒 Engine 🢒 Engine Controls - 3.8L 🢒 Inspection/Maintenance Secondary Air Injection System Set

Description

The purpose of this test is to satisfy the enable criteria necessary to execute inspection/maintenance (I/M) readiness diagnostics for the secondary air injection (AIR) system. The test may be used to set the I/M System Status to YES. The I/M System Status display on the scan tool provides an indication of whether the control module has completed the required tests. The I/M System Status does not indicate that the tests have passed or failed. When all of the diagnostics for a specific system have run and passed, the I/M System Status will update to YES. If a test for a specific system has failed, the I/M System Status will update to YES, indicating a determination was made, even if all of the other tests for that system have not run.

Conditions for Running

Passive Test

    • The start-up engine coolant temperature (ECT) is between 5-80°C (41-176°F).
    • The ECT is between 5-108°C (41-226°F).
    • The intake air temperature (IAT) is between 5-72.5°C (41-162.5°F).
    • The mass air flow (MAF) is less than 35 g/s.
    • The air-fuel ratio is more than 12.1:1
    • The manifold absolute pressure (MAP) is more than 50  kPa.
    • The battery voltage is more than 10.2 volts.

Active Test

    • Failed or inconclusive passive test
    • The engine load is less than 80 percent.
    • The engine speed is more than 1,000 RPM.
    • The engine is operating in Closed Loop fuel control.

Diagnostic Aids

The AIR pumps generally operate once per ignition cycle, usually upon initial start up before the engine goes into Closed Loop fuel control. Some systems will perform a Passive Diagnostic Test at this time. The Active Diagnostic Test is performed after the engine goes into Closed Loop fuel control. On vehicles that perform a Passive Test, the Active Test will only run if the Passive Test fails or is indeterminate. The Active Test may not run if the Passive Test passes.

If there is an impending failure, the system may require more time to run the diagnostic than was allotted in the set procedure. If the test does not run after numerous attempts and no DTC is set, review the appropriate scan tool data list and the service information for an indication of why the test does not complete. Some tests may abort due to changes in the conditions while the test is running. For example, changes in engine load such as a cooling fan or an A/C compressor clutch turning ON may cause the test to abort.

Step

Action

Yes

No

1

Did you perform the Inspection/Maintenance (I/M) System Check?

Go to Step 2

Go to Inspection/Maintenance (I/M) System Check

2

  1. Ensure that the vehicle is within the Conditions for Running specified in the supporting text.
  2. Turn OFF all of the accessories, e.g., A/C, blower fan, etc.
  3. Start the engine and allow the engine to idle for 2 minutes.

    4. Caution: Refer to Road Test Caution in the Preface section.

    Important:  In order for the Active Test to run, the vehicle must operate in the following conditions:

  4. Acceleration at part throttle to 72 km/h (45 mph) with this speed maintained for 3 minutes or until the I/M System Status indicator updates to YES.
  5. Review the I/M System Status display with a scan tool.

Did the AIR System Status update to YES?

Go to Step 5

Go to Step 3

3

Observe the DTC Information with a scan tool.

Does the scan tool indicate any failed DTCs?

Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

Go to Step 4

4

  1. Refer to the Inspection/Maintenance (I/M) System DTC Table to determine which DTCs are required to run in order to complete this test.
  2. Observe the Not Ran Since Code Cleared display with a scan tool.
  3. Determine which of the DTCs required for a YES status has not run.
  4. Enter the DTC number in the Specific DTC menu of the scan tool.
  5. Operate the vehicle within the Conditions for Running the DTC located in the supporting text for the diagnostic table of the DTC.
  6. Repeat the procedure until the scan tool indicates the diagnostic test has run. This may take up to 2 hours.
  7. Repeat steps 4-6 for any additional required DTCs that have not run.
  8. Observe the I/M System Status display with a scan tool.

Did the AIR System Status update to YES?

Go to Step 5

Go to Diagnostic Aids

5

Observe the Emission Related DTC portion of the I/M System Status display with a scan tool.

Does the scan tool indicate any Emission Related DTCs set?

Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

System OK