DTC Confirmation Test

Ensure intake air temperature is 18°F (-8°C) or more, vehicle is at an altitude of 8000 feet or below, engine coolant temperature is at 18-230°F (-8-110°C), and barometric pressure is 75 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Using scan tool, clear DTCs. See CLEARING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. Drive vehicle at speeds of 40 MPH or more until engine is completely warmed up, and then drive for an additional 8 minutes. Increase vehicle speed to 60-70 MPH, and the allow vehicle to coast to a stop. Using scan tool, check for current or pending DTCs P0151 or P0152. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If DTC resets, go to DIAGNOSIS & REPAIR PROCEDURE .

If DTCs are not set, using scan tool, check completion status of HO2S MONITORING TEST in READINESS TESTS mode. If testing has not been completed, drive vehicle at speeds of 35 MPH or more for 2 minutes or more. Stop vehicle and allow it to idle for one minute. Using scan tool, check for current or pending DTCs P0151 and P0152. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If DTC does not reset, perform visual inspection of intake system. Check for intake air leaks, loose or poor vacuum hose and wiring harness connections. Check for intermittent problem. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. If problem is found, repair as necessary. After repair, repeat DTC confirmation procedure starting at beginning. If DTC resets, go to DIAGNOSIS & REPAIR PROCEDURE .