What does NOx mean on a truck dashboard?

[LeMalia]

NOx in vehicles refers to nitrogen oxides, which are brown exhaust gases with a pungent odor produced in large quantities when the engine is under certain loads. When the engine exhaust is first emitted, the NO present in the gas has relatively low toxicity, but it is easily oxidized into more toxic nitrogen oxides such as NO2. After entering the alveoli, NOx can form nitrous acid and nitric acid, causing severe irritation to lung tissue. The following are reasons for excessively high NOx emissions: 1. The DEGR system is not functioning properly; 2. Faulty input sensors in the ignition timing control system result in an overly lean air-fuel mixture; 3. The engine operating temperature is too high; 4. The intake air temperature is too high, requiring inspection of the intake air temperature regulation system and the turbocharged intercooler system, among others.