96 Chevrolet Impala Slow Start with OBD2 Code P0153 - O2 Sensor Bank 2 Sensor 1 Issue
My 1996 Chevrolet Impala has started exhibiting slow engine cranking, accompanied by a check engine light and diagnostic code P0153. The O2 sensor in Bank 2, Sensor 1 was recently replaced due to a reported lean condition. The vehicle has 159,000 miles and retains original vacuum lines, starter, and alternator components. Despite the replacement, the issue persists. I'm seeking advice on potential root causes, especially given that P0153 is not actually a lean code but rather indicates a malfunction in the oxygen sensor reading.
For 96 Impala models with 3.5L or 3.9L engines: Why was the O2 sensor replaced? Are there any other diagnostic trouble codes present? Did you install an AC Delco sensor—this is a front bank sensor? What does your OBD2 scanner show for Bank 2, Sensor 1 readings? Reference: http://www.obd-codes.com/p0153