GM Service Manual Online
For 1990-2009 cars only

Description

The purpose of the I/M Complete System Set Procedure is to satisfy the enable criteria necessary to execute all of the I/M readiness diagnostics, and to 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 1 or when all of the I/M System Status indicators are set to NO.

Conditions for Running

    • The barometric pressure is more than 72 kPa (10.4 psi).
    • The engine coolant temperature (ECT) is between 5-120°C (41-248°F).
    • The intake air temperature (IAT) is between -6 to +200°C (21-392°F).
    • The battery voltage is between 9-18 volts.
    • The fuel level is between ¼ - ¾.

Diagnostic Aids

Rough road conditions may prevent some of the tests from running. Extreme high or low ambient temperatures may prevent tests such as heated oxygen sensor (HO2S) heater and evaporative emission (EVAP) system from initiating. If a step is interrupted before completion, perform the remaining portion of the set procedures. Any portion of the set procedure that requires the engine at the operating temperature may be repeated. This procedure allows most of the diagnostics to run, and the remaining tests can be performed using the individual System Set Procedures.

If the vehicle has recently run, start this procedure at step 3. This method will allow the tests that require the engine at operating temperature to run. Using this method allows shorter cool down periods if the tests requiring a cold start do not initiate.

The scan tool can be used to monitor each of the I/M System Status indicators during the I/M Complete System Set Procedure. When all of the indicators for a test step have updated to YES, testing can move on to the next step even if the remaining portion of the test is not complete. For example, step 3 is designed to run the EVAP, the AIR, and the HO2S tests. The procedure instructs the technician to operate the vehicle in the enable conditions for 6 minutes. If all 3 tests have updated to YES within 4 minutes, it is not necessary to continue with the enable conditions and testing can advance to the next step.

Test Description

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

  1. You must perform the I/M System Check before performing this test. Failure to do so may result in difficulty updating the status to YES.

  2. This step is to run the HO2S Heater Tests and to initiate the EVAP System Test.

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

  3. This step is to run the EVAP, the 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 are achieved. The Oxygen sensor tests begin once the engine is at the operating temperature, in Closed Loop Fuel Control, and a calibrated amount of time has elapsed.

  4. This step is to run the 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. 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.

  6. Perform the individual system test for any of the systems that do not update to YES.

  7. The I/M System Status only reports on whether or not a diagnostic has run, not the outcome of the test. If any emission related DTC sets after the tests are complete, the DTC will require diagnosis.

Step

Action

Value(s)

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 HO2S heaters. After verifying the enable criteria, turn OFF the ignition for approximately 5 minutes in order 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, including the A/C, and the blower fan.
  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.
  7. Allow the engine to idle for the specified time.

Is the action complete?

2 minutes

Go to Step 3

--

3

Caution: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.

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 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

Caution: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.

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

  1. The vehicle speed reduced to 72 km/h (45 mph), with this speed maintained for 1 additional minute.
  2. Four decelerations of 25 seconds each from 72 km/h (45 mph) while the following criteria are maintained:
  3. • 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 the speed is maintained for 15 seconds.

Is the action complete?

--

Go to Step 5

--

5

Caution: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.

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

  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. The engine idling for 2 minutes while the following criteria are maintained:
  4. • 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

With a scan tool, observe the I/M System Status display.

Did all of the I/M System Status indicators update to YES?

--

Go to Step 7

Go to

7

With a scan tool, observe the Emission Related DTC portion of the I/M System Status display.

Does the scan tool indicate that any emission related DTCs set?

--

Go to Inspection/Maintenance (I/M) System DTC Table

System OK