宝马3系318i/320i右后氧传感器 11787570481 0258006993 精准排气监控

BMW 3 Series 318i/320i (N46/N43 engines) rear oxygen sensor, OEM numbers 11787570481 and 0258006993. This replacement uses a high-temperature ceramic substrate and dual laser-welded structure, benchmarked against original factory durability to withstand the high temperatures and vibrations of the exhaust system. Functionally monitors the oxygen content after the catalytic converter, feeds back to the ECU to adjust air-fuel ratio, ensuring emissions compliance and stable fuel economy. Installation requires a special socket to remove the old part; difficulty is moderate.