Technician A says that advancing diesel fuel injection timing by one degree can produce greatly increased NOx in the end gas. Technician B says that retarding diesel fuel injection timing tends to increase the output of HC in the exhaust gas. Who is right?

Question

Quizplus · Accepted Answer

Advancing diesel fuel injection timing increases combustion temperature, leading to higher NOx emissions. Retarding the timing results in incomplete combustion, increasing HC (hydrocarbons) in the exhaust.

Technician a Says That Advancing Diesel Fuel Injection Timing by One