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Home >> Pontiac >> 2005 >> Grand Prix Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 3.8L - Troubleshooting & Diagnosis >> Inspection/Maintenance (I/M) Complete System Set Procedure >> Test Description
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Test Description

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

  1. 1:  Perform the I/M System Check before performing this test. Failure to do so may result in difficulty updating the status to YES.
  2. 2:  This step runs the HO2S Heater Tests and initiate the EVAP System Test. Preprogramming the scan tool will reduce the amount of time the oxygen sensor heaters operate while verifying the enable criteria. The engine control module considers the engine to be cold if the following conditions are met:
    • ECT less than 35°C (95°F)
    • ECT and IAT are within 6°C (11°F) of each other at start up
  3. 3:  This step runs the EVAP, AIR and the Oxygen Sensor Tests. The EVAP Test begins once the engine coolant reaches a calibrated temperature. The AIR Test, if equipped, begins shortly after Closed Loop and the indicated speed is achieved. The Oxygen Sensor Tests begin once the engine is at operating temperature, in Closed Loop Fuel Control, and a calibrated amount of time has elapsed.
  4. 4:  This step runs the exhaust gas recirculation (EGR) Tests. The EGR Tests are run during a gradual deceleration with a closed throttle. The vehicle speed is required in order to maintain a high, steady manifold absolute pressure (MAP) signal.
  5. 5:  This step runs the Catalyst Tests. This test runs during the idle period immediately following a cruise period that meets a minimum calibrated RPM and time period.
  6. 6:  Perform the individual system test for any of the systems that do not update to YES.
  7. 7:  The I/M System Status only reports on whether or not a diagnostic has run, not what the outcome of the test was. If any emission related DTC sets after the tests are complete, the DTC will require diagnosis.
Inspection/Maintenance (I/M) Complete System Set Procedure

Step Action Values 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 
    IMPORTANT: Whenever the ignition is turned ON, ignition positive voltage is supplied to the heated oxygen sensor (HO2S) heaters. After verifying the enable criteria, turn OFF the ignition for approximately 5 minutes to allow the sensors to cool before continuing with the test. Once the engine is started, DO NOT turn the engine OFF for the remaining portion of the set procedure.
  1. Preprogram the scan tool with the vehicle information before the ignition is turned ON.
  2. Ensure that the vehicle is within the Conditions for Running specified in the supporting text.
  3. Turn OFF all of the accessories, such as the A/C, blower fan, etc.
  4. Set the vehicle parking brake.
  5. Verify the transmission is in Park for automatic transmissions and Neutral for manual transmissions.
  6. Start the engine.
  7. Allow the engine to idle for the specified time.
Is the action complete?		 2 minutes Go to Step 3  -
3  The vehicle must operate in the following conditions in order for the next group of tests to run:
  1. Acceleration at part throttle to 90 km/h (55 mph) with this speed maintained until the engine reaches operating temperature. This may be up to 8-10 minutes depending on the start up coolant temperature.
  2. Continued operation under these conditions for an additional 6 minutes.

Is the action complete?		 - Go to Step 4  -
4  The vehicle must operate in the following conditions in order for the next group of tests to run:
  1. The vehicle speed is reduced to 72 km/h (45 mph) with this speed maintained for one additional minute.
  2. Four decelerations of 25 seconds each from 72 km/h (45 mph) while the following criteria is maintained:
    • The throttle is closed.
    • No brake application on either manual or automatic transmission
    • No clutch actuation on a manual transmission
    • No manual downshift
    • The vehicle speed remains above 40 km/h (25 mph).
    • After each deceleration period, the vehicle is returned to 72 km/h (45 mph) under part throttle acceleration and speed is maintained for 15 seconds.

Is the action complete?		 - Go to Step 5  -
5  The vehicle must operate in the following conditions in order for the next group of tests to run:
  1. Acceleration at part throttle to 75-89 km/h (45-55 mph) with this speed maintained for 2 minutes
  2. Deceleration to 0 km/h (0 mph)
  3. Engine idling for 2 minutes while the following criteria is maintained:
    • The service brake is depressed.
    • The automatic transmission is in Drive.
    • The manual transmission is in neutral with the clutch pedal depressed.

Is the action complete?		 - Go to Step 6  -
6  Observe the I/M System Status display with a scan tool.
Did all of the I/M System Status indicators update to YES?		 - Go to Step 7  Perform the set procedure for the system that has not updated. Refer to Inspection/Maintenance (I/M) System DTC Table 
7  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
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