LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Oldsmobile >> 2003 >> Aurora >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Drive Cycles >> Inspection/Maintenance EGR System Set Procedure >> Diagnostic Procedures
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Procedures

  1. Did you perform the Inspection/Maintenance (I/M) system Check? If yes, go to next step. If no, go to INSPECTION/MAINTENANCE SYSTEM CHECK .
  2. WARNING: Road test a vehicle under safe conditions and while obeying all traffic laws. DO NOT attempt any maneuvers that could jeopardize vehicle control and could result in serious personal injury and vehicle damage.
  3. Ensure that the vehicle is within the Conditions for Running. Turn OFF all of the accessories (e.g., A/C, blower fan, etc.). Start and allow engine to idle. Accelerate at part throttle to 45 MPH with this speed maintained for one minute. Four decelerations of 25 seconds each from 45 MPH while the following criteria is maintained: Throttle is closed, no brake application, no manual downshift, vehicle speed remains greater than 25 MPH. After each deceleration period, vehicle is returned to 45 MPH under part throttle acceleration and speed is maintained for 15 seconds. With a scan tool, observe the I/M System Status display. Did the EGR System Status update to YES? If yes, go to step  5. If no, go to next step.
  4. Using scan tool, observe DTC Information. Does the scan tool indicate any failed DTCs? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, go to next step.
  5. Refer to the Inspection/Maintenance (I/M) System DTC Table to determine which DTCs are required to run in order to complete this test. See INSPECTION/MAINTENANCE SYSTEM DTCS  under INSPECTION/MAINTENANCE COMPLETE SYSTEM SET PROCEDURE. Using scan tool, observe the Not Ran Since Code Cleared display. Determine which of the DTCs required for a YES status has not run. Operate vehicle within the Conditions for Running DTC. Repeat the procedure until the scan tool indicates the diagnostic test has run or for any additional required DTCs that have not run. Using scan tool, observe the I/M system Status display. Did the EGR system Status update to YES? If yes, go to next step. If no, see DIAGNOSTIC AIDS .
  6. Using scan tool, observe the emission related DTC portion of I/M system Status display. Does the scan tool indicate any Emission Related DTCs set? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.