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Home >> Chevrolet >> 2002 >> Impala LS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self-Diagnostics - 3.8L >> Inspection/Maintenance Procedures >> Inspection/Maintenance Exhaust Gas RECIRCULATION System Set Procedure >> Procedure
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Inspection/Maintenance Exhaust Gas RECIRCULATION System Set Procedure: Procedure

  1. Perform INSPECTION/MAINTENANCE SYSTEM CHECK . After performing inspection/maintenance system check, go to next step.
    2. CAUTION: 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.
  2. Ensure vehicle is operating within Conditions for Running. Turn off all of accessories. Start engine and allow to idle. Accelerate at part throttle to 45 MPH and maintain speed for one minute. Perform 4 decelerations of 25 seconds each from 45 MPH while following criteria is maintained:
    • 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 more than 25 MPH.

    After each deceleration period, vehicle is returned to 45 MPH under part throttle acceleration and speed is maintained for 15 seconds. Using scan tool, observe I/M SYSTEM STATUS display. If EGR system status updates to YES, go to step  5. If EGR system status did not update to YES, go to next step.

  3. Using scan tool, observe DTC information. If scan tool indicates any failed DTCs, see DIAGNOSTIC TROUBLE CODE INDEX  table under DIAGNOSTIC TROUBLE CODE DEFINITIONS. If scan tool does not indicate any failed DTCs, go to next step.
  4. Using scan tool, observe NOT RAN SINCE CODE CLEARED display to determine if DTCs P0401, P0404, P0405 and P1404 have run. For those DTCs that have not run, see Conditions for Running DTC in 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 EGR system status updated to YES, go to next step. If EVAP system status did not update to YES, see DIAGNOSTIC AIDS .
  5. Using scan tool, check for DTCs. If scan tool indicates any DTCs are set, see DIAGNOSTIC TROUBLE CODE DEFINITIONS .
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