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 or 40 MPH for 5 minutes. Stop vehicle and allow it to idle for one minute. Drive vehicle with engine speed at 2000-3000 RPM for 30 seconds or more. Stop vehicle. Using scan tool, check for current or pending DTC P0121. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If DTC resets, go to DIAGNOSIS & REPAIR PROCEDURE .