What are the causes of excessive NOx emissions in vehicles?
2 Answers
The causes of excessive NOx emissions in vehicles are: 1. Blocked fuel lines or fuel injectors, or insufficient fuel injection, which leads to excessive oxygen content in the engine. The immediate emissions of CH and CO are too low to reduce NOx, resulting in excessive vehicle exhaust emissions; 2. Failure of the three-way catalytic converter to catalyze chemical reactions between CH, CO, and NOx, leading to excessive vehicle exhaust emissions. The hazards of emission system malfunctions are: 1. Excessive carbon buildup; 2. Compromised driving safety and reduced engine lifespan; 3. Engine overheating, causing sintering or detachment of the three-way catalytic converter carrier and increased exhaust resistance; 4. Excessive emission of harmful substances.
Oh, I found that excessive NOx emissions from cars are usually caused by the engine's combustion temperature being too high, where nitrogen and oxygen combine at high temperatures to form nitrogen oxides. Another common reason is an imbalance in the air-to-fuel ratio; if there's too much air and too little fuel, the mixture becomes too lean, leading to this issue. Older cars are particularly prone to problems, as components in the exhaust system, like the EGR, may fail to recirculate exhaust gases for cooling, or the catalytic converter may become clogged and ineffective. Driving habits also play a role—frequent rapid acceleration or long-distance driving that overheats the engine can exacerbate the problem. Poor fuel quality affects combustion efficiency, further increasing emissions. It's recommended to regularly maintain and inspect these components, use high-quality fuel, and maintain a reasonable air-fuel mixture to effectively lower temperatures and control emissions. In summary, excessive NOx not only pollutes the air but also poses health risks, so it must be addressed promptly.
