Code Enable Criteria

• Engine has been running in closed loop fuel control for at least 60 seconds.
• Engine speed is 1000-3000 RPM (except Park Avenue). Engine speed is 550-3000 RPM (Park Avenue).
• Engine Coolant Temperature (ECT) is more than 122°F (50°C) (except Park Avenue). Engine Coolant Temperature (ECT) is greater than 167°F (70°C) (Park Avenue).
• Mass Airflow (MAF) is 10-30 grams/second (except Park Avenue). MAF is between 8-35 grams/second (Park Avenue).
• DTCs P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0125, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0410, P0440, P0442, P0443, P0446, P0449, or P1441 are not set.

For Bonneville and LeSabre VIN K, DTC sets when HO2S 1 lean-to-rich average transition response time during sample period was more than 140 milliseconds, or rich-to-lean average transition response time during sample period was more than 107 milliseconds.

For Bonneville and LeSabre VIN 1, DTC sets when HO2S 1 lean-to-rich average transition response time during sample period was more than 130 milliseconds, or rich-to-lean average transition response time during sample period was more than 110 milliseconds.

For Grand Prix, Impala, Monte Carlo, Park Avenue and Regal, HO2S 1 lean-to-rich average transition response time during sample period was longer than 145 milliseconds, or rich-to-lean average transition response time during sample period was longer than 135 milliseconds.