GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 HUMMER 🢒 2007 🢒 H3 🢒 Engine 🢒 Engine Controls and Fuel - 3.7L 🢒 Inspection/Maintenance Evaporative Emission System Set

Description

The purpose of this procedure is to satisfy the enable criteria necessary to execute an inspection/maintenance (I/M) system monitor for the evaporative emission (EVAP) system. The system monitor is comprised of the test results from one or more DTCs. This procedure may be used to set the EVAP I/M System Status display on the scan tool to YES. The EVAP I/M System Status display indicates whether or not the control module has completed the system monitor. The system monitor completes when either all DTCs comprising the monitor run and pass, or any DTC comprising the monitor illuminates the malfunction indicator lamp (MIL). If one of the DTCs comprising the monitor is set and the MIL is not illuminated, the necessary trips are required to illuminate the MIL before the monitor will complete.

If the system monitor runs during one drive cycle, 17 hours must elapse, regardless of whether the vehicle is driven or not. Then, the monitor will run again during the next drive cycle in which the conditions for running are met. Once the monitor has run during the third drive cycle, the EVAP I/M System Status display will be updated to YES.

Conditions for Running
    • The difference between the start-up engine coolant temperature (ECT) and the start-up intake air temperature (IAT) is less than 8°C (14.4°F).
    • The barometric pressure (BARO) is more than 74 kPa.
    • The start-up ECT is between 4-30°C (39-86°F).
    • The start-up IAT is between 4-30°C (39-86°F).
    • The fuel level is between 15-85 percent.
    • The battery voltage is between 11-18 volts.
    • The fuel level does not increase more than 10 percent during the drive cycle.
    • The vehicle has been driven at least 5 km (3.2 miles) during the drive cycle.
    • The ECT is more than 70°C (158°F).

Diagnostic Aids

Extreme high or low ambient temperatures may prevent DTCs from initiating. Rough road conditions, a damaged or improperly connected fuel cap, and high fuel volatility may cause DTCs to abort or fail. High fuel volatility usually means that the fuel in the vehicle has a high volatility than what is appropriate for the ambient temperatures. This can occur when winter fuel is used during warm temperatures. DTCs may also abort due to changes in the conditions while running. for example, changes in engine load, such as a cooling fan or A/C compressor clutch turning ON, may cause a DTC to abort. Failed or aborted DTCs will require the vehicle to cool down in order to meet the conditions for running another drive cycle.

If there is an impending failure, the system may require more time to run than was allotted in the procedure. If any DTCs do not run after numerous attempts and no DTC is set, review the scan tool data list and conditions for running. This will give an indication of why the DTCs do not complete. If the EVAP I/M System Status does not update to YES, the procedure can be repeated until a YES status is achieved.

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 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. Important: Once the engine is started, DO NOT turn the engine OFF for the remainder of the procedure.

  3. Start and allow the engine to idle for 2 minutes.

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

    Important: In order for this 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 until the engine reaches operating temperature. This may be up to 10 minutes depending on the start-up coolant temperature.
  5. Continue the operating conditions for an additional 6 minutes after the engine reaches operating temperature.
  6. Deceleration to 0 km/h (0 mph).
  7. Engine idling for 2 minutes.

    8. Important: Ensure that the ignition remains OFF for 1 hour in order for the control module to perform vacuum testing.

  8. Turn OFF the ignition for 1 hour.
  9. After 1 hour, turn ON the ignition.

Important: At least 3 drive cycles, with a minimum of 17 hours between drive cycles, are required for the EVAP System Status to update to YES. Repeat numbers 1-9 of this step until the minimum requirement of drive cycles is met.

Did the EVAP 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

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 update the EVAP I/M System Status to YES.
  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 numbers 4 and 5 of this step for any additional required DTCs that have not run.
  7. Observe the I/M System Status display with a scan tool.

Did the EVAP 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

System OK