For 1990-2009 cars

### 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. Service Bay Tests are included on the scan tool for some systems depending upon vehicle make and model. The test is designed to allow the EVAP Diagnostic Tests to run in service bay conditions. Ensure the vehicle meets the requirements listed in Conditions for Running before performing either EVAP System Test. Failure to meet the necessary requirements may produce inaccurate test results.

### Conditions for Running

#### Non Scan Tool Service Bay Test equipped vehicles

• | The barometric pressure (BARO) is more than 75 kPa.

• | The engine coolant temperature (ECT) is at least 70°C (158°F) after engine warm up.

• | The fuel level is between ¼ and ¾.

• | The battery voltage is between 10.5-16 volts.

• | The vehicle has been driven for at least 20 minutes.

• | The test will initiate only after a cold start. The control module considers the engine to be cold if the engine coolant temperature (ECT) is below 2°C (35°F).

### Diagnostic Aids

Extreme high or low ambient temperatures may prevent the EVAP System Tests from initiating. Performing a visual inspection prior to running the EVAP System Set Procedure 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.

The I/M System Status does not indicate whether the test has passed or failed, only that a decision was made. 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 required tests have not run. When a failure occurs, the Emission Related DTC portion of the I/M System Status display will indicate the malfunction indicator lamp (MIL) is requested. The I/M System Status also registers the number of diagnostic trouble codes (DTCs).

The first failure of a type B DTC does not constitute a final determination of pass or fail, and will not update the I/M System Status to YES. A second trip is required, and all the conditions to run must be met in order for the test to run again. These conditions may include a partial to complete engine cool down.

The I/M System Status will update only when an emission related DTC fails the second time, or when all of the tests pass.

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.

If a diagnostic test is difficult to run, maintain necessary enable conditions until the system status updates to YES.

### Test Description

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

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

2. The EVAP System test runs immediately following the idle period.

3. This step is to identify a first failure of a type B DTC. A DTC only appears on the I/M System Status display when it becomes a MIL illuminating DTC. This occurs on the second failure of a type B DTC. A first failure of a type B DTC will not allow the I/M System Status to update to YES. Refer to Diagnostic Aids.

4. This step is to help identify any unique or unusual criteria required to run the diagnostic test in the event the universal set procedure does not. This information is located in the service information under Conditions for Running the DTC.

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 | 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.

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

3. Start and idle the engine.

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 result in serious personal injury and vehicle damage.

Important: In order for this test to run, the vehicle must operate in the following conditions:

4. Idle the engine until the engine reaches operating temperature of at least 70°C (158°F). This may be up to 8-10 minutes depending on the start up coolant temperature.
5. Acceleration at part throttle to 48-80 km/h (30-50 mph) and cruise for 3 minutes after the engine reaches operating temperature.
6. Deceleration to 0 km/h (0 mph).
7. Engine idling for 1 minute while the following criteria is maintained:

• | Service brake depressed

• | Automatic transmission in drive

• | Manual transmission in neutral with the clutch pedal depressed

8. Accelerate at part throttle to 64-72 km/h (40-45 mph) with this speed maintained for 1 minute.
9. With a scan tool, observe the I/M System Status display.

Did the EVAP System Status update to YES?

Go to Step 5

Go to Step 3

3 | With a scan tool, observe the DTC Information. Does the scan tool indicate any failed DTCs? | Go to Diagnostic Trouble Code (DTC) List | 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 complete this test.
2. Operate the vehicle within the Conditions for Running the DTC, located in the supporting text for the diagnostic table of the DTC.
3. Repeat the procedure until the scan tool indicates the diagnostic test has run.
4. With a scan tool, observe the I/M System Status display.

Did the EVAP System Status update to YES?

Go to Step 5

Go to Diagnostic Aids

5 | With a scan tool, observe the Emission Related DTC portion of the I/M System Status display. Does the scan tool indicate any Emission Related DTCs set? | Go to Diagnostic Trouble Code (DTC) List | System OK