GM Service Manual Online
For 1990-2009 cars only

Description

The purpose of the inspection/maintenance (I/M) complete system set procedure is to satisfy the enable criteria necessary to execute all of the I/M readiness diagnostics, and complete the trips for those particular diagnostics. When all diagnostic tests are completed, the I/M System Status indicators are set to YES. Perform this test when more than one or all of the I/M System Status indicators are set to NO.

Conditions for Running

Cold Start

    • The barometric pressure (BARO) is more than 74 kPa.
    • The engine coolant temperature (ECT) is below 30°C (86°F).
    • The intake air temperature (IAT) is between 4-30°C (39-86°F).
    • The difference between the IAT and the ECT is 6°C (10.8°F) or less.
    • The battery voltage is between 10-18 volts.
    • The fuel level is between 15-85 percent.

Test Description

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

  1. This step is to run the heated oxygen sensor (HO2S) Heater Tests and initiate the evaporative emission (EVAP) System Test.

    Preprogramming the scan tool will reduce the amount of time the oxygen sensor heaters operate while verifying the enable criteria.

  2. This step is to run the EVAP, 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.

  3. This step is to run 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.

  4. This step is to run the Catalyst Tests. This test runs during the idle period immediately following a cruise period that meets a minimum calibrated RPM and time period.

  5. 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.

Step

Action

Values

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

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 the vehicle is within the Conditions for Running specified in the supporting text.
  3. Turn OFF all of the accessories, e.g., 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 and allow it to idle for the specified time.

Is the action complete?

2 minutes

Go to Step 3

--

3

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

In order for the next group of tests to run, the vehicle must operate in the following conditions:

  1. Acceleration at part throttle to 72 km/h (45 mph) with this speed maintained until the engine reaches operating temperature--This may be up to 10 minutes depending on the start-up coolant temperature.
  2. Continue operation under these conditions for an additional 3 minutes.

Is the action complete?

--

Go to Step 4

--

4

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

In order for the next group of tests to run, the vehicle must operate in the following conditions:

  1. Accelerate to 89 km/h (55 mph) with this speed maintained for one additional minute.
  2. Decelerate to 48 km/h (30 mph) while the following criteria is maintained:
  3. • The throttle is closed.
    • There is NO brake application on either manual or automatic transmission.
    • There is NO clutch actuation on a manual transmission.
    • There is NO manual downshift.

Is the action complete?

--

Go to Step 5

--

5

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

In order for the next group of tests to run, the vehicle must operate in the following conditions:

  1. Acceleration at part throttle to 90 km/h (55  mph) with this speed maintained for 5 minutes.
  2. Deceleration to 0 km/h (0 mph).
  3. Engine idling for 2 minutes while the following criteria is maintained:
  4. • Service brake depressed
    • Automatic transmission in Drive
    • Manual transmission 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

Go to the I/M System Set Procedure for the indicated systems that have not updated

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