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Home >> Chevrolet >> 2001 >> Chevy Express G3500, Van Cargo Extended, 6.5 F >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics - 6.5L >> Inspection/Maintenance Procedures >> Inspection/Maintenance Complete System Set PROCEURE >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform powertrain diagnostic system check. See POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing powertrain diagnostic system check, go to next step.
    2. NOTE: Once engine is started, DO NOT turn engine OFF for the remaining portion of the set procedure.
  2. Ensure vehicle meets conditions under DESCRIPTION . Turn off all accessories, such as A/C, blower fan, etc. Set vehicle parking brake. Ensure transmission is in Park (A/T) or Neutral (M/T). Start and operate engine at idle for 2 minutes, then go to next step.
    3. 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.
  3. Accelerate at part throttle to 50 MPH with this speed maintained until engine reaches operating temperature. This may be up to 8-10 minutes depending on start-up coolant temperature. Continue operation under these conditions for an additional 3 minutes, then go to next step.
  4. Accelerate at 75 percent throttle until a speed of 68 MPH is attained. Decelerate zero MPH. Operate engine at idle for 2 minutes while the following criteria is maintained:
    • Service brake depressed.
    • Transmission in Drive (A/T).
    • Transmission in Neutral with clutch pedal depressed (M/T).

    After performing procedures, go to next step.

  5. Using scan tool, observe I/M System Status display. If all I/M System Status indicators update to YES, go to next step. If all I/M system status indicators do not update to YES, repeat procedure.
  6. Using scan tool, observe emission related DTC portion of I/M System Status display. If scan tool indicates any emission related DTCs, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If scan tool does not indicate emission related DTCs, system is okay.
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