DTC Confirmation Test

Ensure intake air temperature is between 6.8°F and 158°F (-14°C and 70°C), vehicle is at an altitude lower than 9150 feet, 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. Start the engine and warm to normal operating temperature. Increase vehicle speed to 50-60 MPH (engine speed: 2500-3000 RPM). Keep this speed for 1 minute (throttle valve operation is kept constant). Stop vehicle and using scan tool, check for current or pending DTCs P0153. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If DTC resets, go to DIAGNOSIS & REPAIR PROCEDURE .

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 .