No, the bad one should be replaced.
1) the effect on engine
If the NOx sensor is fault, it will cause a breakdown to the engine,then multiple trouble lights will be lightened, and ECU will record the fault, so we need to change a good one, and delete the fault code to ensure the driving.
2) the disorder of combustion control
As an important part of the electronic fuel injection system, a faulty NOx sensor will cause a disorder to the combustion control system, then lead to the weak acceleration of the engine, idling
and vibration, or even can’t start the vehicle, etc.
