Chevrolet Buick Cadillac GMC Hummer Oxygen Sensor 234-4337

universal KLP oxygen sensor (OEM 234-4337) directly replaces OEM 12589321; widely suitable for Chevrolet, Buick, Cadillac, GMC, and Hummer in various general-use models. Installed in exhaust system to monitor oxygen content and adjust air-fuel ratio, addressing high fuel consumption, weak acceleration, or excessive emissions; especially suitable for cars with over 100k km. If MIL is on, idle unstable, or exhaust smells aggressive, sensor aging recommended to replace.