Diesel Engine Topics start with today’s diesel engines are extremely sophisticated and difficult to diagnose.
The most outstanding feature of the diesel engine is its efficiency. By compressing air rather than using an air-fuel mixture, the diesel engine is not limited by the preignition problems that plague high-compression spark-ignition engines.
Thus, higher compression ratios can be achieved with diesel engines than with the spark-ignition variety. The principal drawback of diesel engines is their emission of air pollutants. These engines typically discharge high levels of particulate matter (soot), reactive nitrogen compounds (commonly designated NOx), and odour compared with spark-ignition engines.