Description
The purpose of this test is to satisfy the enable criteria necessary to execute I/M readiness diagnostics for the evaporative emission (EVAP) system. The test may be used to set the I/M System Status indicators to YES. The I/M System Status Display on the scan tool provides an indication of whether the control module has completed the required tests. The I/M System Status does not indicate that the tests have passed or failed. When all of the diagnostics for a specific system have run and passed the I/M System Status will update to YES. If a test for a specific system has failed, the I/M System Status will update to YES, indicating a determination was made, even if all of the other tests for that system have not run. Performing a visual inspection prior to running the EVAP test may prevent having to repeat the test. A failed or aborted test will require the vehicle to cool down in order to meet the enable criteria to run another test.
Conditions for Running
| • | The barometric pressure (BARO) is more than 75 kPa. |
| • | The engine coolant temperature (ECT) is 4-30°C (39-86°F). |
| • | The intake air temperature (IAT) is between 4-30°C (39-86°F). |
| • | The fuel level is between ¼ and ¾. |
| • | The battery voltage is between 11-16 volts. |
| • | The engine is in Closed Loop fuel control. |
| • | The vehicle has been driven for 17 minutes. |
Diagnostic Aids
Extreme high or low ambient temperatures may prevent the EVAP System Tests from initiating. Performing a visual inspection prior to running the test may prevent having to repeat the test. A loose fuel cap may cause a test to abort or fail and prevent the I/M System Status from updating. A failed or aborted test will require the vehicle to cool down in order to meet the enable criteria to run another test.
If there is an impending failure, the system may require more time to run the diagnostic than was allotted in the set procedure. If the test does not run after numerous attempts and no DTC is set, review the appropriate scan tool data list and the service information for an indication of why the test does not complete. Some tests may abort due to changes in the conditions while the test is running. For example, changes in engine load, such as a cooling fan or an A/C compressor clutch turning ON, may cause the test to abort.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Inspection/Maintenance (I/M) System Check? | -- | Go to Step 2 | |
2 |
Important: Once the engine is started, DO NOT turn the engine OFF for the remainder of the procedure. 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: 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 Step 4 | |
4 |
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? | -- | System OK |
