What does NOx mean in diesel vehicles?

[BeauRose]

NOx stands for nitrogen oxides. NOx is a type of brown, pungent exhaust gas that is produced in large quantities when the engine is under load. When the engine exhaust is first emitted, the NO present in the gas is less toxic, but it is easily oxidized into other nitrogen oxides such as NO2, which are more toxic. After NOx enters the alveoli, it can form nitrous acid and nitric acid, causing severe irritation to lung tissue. The following are reasons for excessive NOx emissions: 1. The EGR system is not functioning properly; 2. Faulty input sensors in the ignition timing control system leading to an overly lean air-fuel mixture; 3. The engine operating temperature is too high; 4. The intake air temperature is too high, so the intake air temperature control system and intercooler system should be checked.