GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 GMC C Sierra - 2WD 🢒 Engine 🢒 Engine Controls - 4.3L 🢒 Inspection/Maintenance (I/M) Complete System Set Procedure

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 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 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 below 30°C (86°F).
    • The difference between the intake air temperature (IAT) and the engine coolant temperature (ECT) is 8°C (14°F) or less.
    • The battery voltage is between 9-18 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 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.

    2.

  2. 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.

    3.

  3. 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.

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 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.
  6. Start the engine. Allow the engine 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. Accelerate at part throttle to 90 km/h (55 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. Continued operation under these conditions for an additional 6 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. Vehicle speed 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:
    3. • Throttle is closed
    • NO brake application
    • NO manual downshift
    • Vehicle speed remains above 40 km/h (25 mph).
    • After each deceleration period, 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

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 at part throttle to 75-89 km/h (45-55 mph) with this speed maintained for 2 minutes
  2. Decelerate to 0 km/h (0 mph)
  3. Idle the engine for 2 minutes while the following criteria is maintained:
    4. • Service brake is pressed.
    • Automatic transmission is in DRIVE.

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

System OK