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Home >> Chevrolet >> 2001 >> Chevy Express G3500, Van Cargo Extended, 4.3 W >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 4.3L >> Inspection/Maintenance Procedures >> Inspection/Maintenance Catalyst System Set Procedure >> Procedure
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Inspection/Maintenance Catalyst System Set Procedure: Procedure

  1. Perform INSPECTION/MAINTENANCE SYSTEM CHECK . After performing inspection/maintenance system check, go to next step.
  2. WARNING: Road test 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.
  3. Ensure vehicle is operating within enable criteria. Turn all accessories off. Start engine and allow to idle. Operate vehicle in the following manor:
    • Accelerate at part throttle to 55 MPH and maintain speed for 5 minutes.
    • Decelerate to zero MPH and allow engine to idle for 2 minutes while service brake is depressed, A/T in Drive and M/T in neutral with clutch pedal depressed.

    Using scan tool, monitor I/M SYSTEM STATUS. If CATALYST SYSTEM STATUS is YES, go to step  5. If CATALYST SYSTEM STATUS is not YES, go to next step.

  4. Using scan tool, observe DTC information. If scan tool indicates any failed DTCs, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If scan tool does not indicate any failed DTCs, go to next step.
  5. Using scan tool, observe NOT RAN SINCE CODE CLEARED display to determine if DTCs P0420 and P0430 have run. For those DTCs that have not run, see CODE ENABLE CRITERIA under appropriate DTC under DIAGNOSTIC TESTS. Operate vehicle to meet code enable criteria until DTC(s) runs. Using scan tool, observe I/M SYSTEM STATUS display. If catalyst system status updated to YES, go to next step. If catalyst system status did not update to YES, see DIAGNOSTIC AIDS .
  6. Using scan tool, check for DTCs. If scan tool indicates any DTCs are set, see DIAGNOSTIC TROUBLE CODE DEFINITIONS .