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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2003 🢒 DeVille 🢒 Engine 🢒 Engine Controls - 4.6L 🢒 Inspection/Maintenance (I/M) Exhaust Gas Recirculation (EGR) System Set Procedure

Description

The purpose of this test is to satisfy the enable criteria necessary to execute I/M readiness diagnostics for the exhaust gas recirculation (EGR) 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.

Conditions for Running
    • The barometric pressure (BARO) is more than 70 kPa.
    • The engine coolant is at operating temperature, 80-110°C (176-230°F).
    • The intake air temperature (IAT) is less than 50°C (122°F).
    • The idle speed is steady.
    • The system voltage is between 11-18 volts.
    • The transmission state is steady.
    • The vehicle speed is greater than 37 km/h (23 mph).
    • The A/C state is steady.

Diagnostic Aids

The control module only runs the EGR Active Tests during a gradual deceleration with a closed throttle and a vehicle speed above 37 km/h (23 mph). Several deceleration cycles may be necessary in order to accumulate a sufficient number of EGR flow samples. The procedure outlined in the table is for a clear, flat road. If the procedure is performed on a road with a slight down hill grade, the test may acquire the necessary sample counters in one or two decel trips. If the test is interrupted during the procedure, more than ten deceleration cycles may be needed to complete the test. If the status does not update, the test outlined in this procedure can be repeated until the I/M System Status updates to YES.

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

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

    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.

    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 for 1 minute.
  5. Four decelerations of 25 seconds each from 72 km/h (45 mph) while the following criteria is maintained:
    6. • Throttle is closed
    • NO brake application on either manual or automatic transmission
    • NO clutch actuation on a manual transmission
    • 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.
  6. Observe the I/M System Status display with a scan tool.

Did the EGR 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

Go to Step 4

4

  1. Refer to Inspection/Maintenance (I/M) System DTC Table to determine which DTCs are required to run in order to complete this test.
  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 the procedure until the scan tool indicates the diagnostic test has run. This may take up to 2 hours.
  7. Repeat steps 4-6 for any additional required DTCs that have not run.
  8. Observe the I/M System Status display with a scan tool.

Did the EGR 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

System OK