What Is The Difference between Gasoline Engines And Diesel Engines? ​

In automotive power systems, gasoline engines and diesel engines are two mainstream choices, and they have significant differences in working principles, performance, and other aspects. The following provides a detailed analysis from multiple dimensions:

1、 Different working principles

Gasoline engines use spark ignition, where air and gasoline mix to form a combustible mixture during the intake stroke. After entering the cylinder, the mixture is compressed and then ignited by an electric spark generated by a spark plug, which drives the piston to do work. Diesel engines, on the other hand, use compression ignition, which only draws in air and undergoes high-intensity compression to raise the air temperature to the ignition point of diesel. Then, diesel is injected into the cylinder through fuel injectors, and it burns on its own after coming into contact with high-temperature air.

2、 Differences in fuel characteristics

Gasoline has strong volatility and a low ignition point (about 220 ℃), but its energy density is relatively low; Diesel has poor volatility and a high ignition point (about 250 ℃), but it has a higher energy density. This makes diesel engines generally more fuel-efficient than gasoline engines, and at the same displacement, diesel cars have a longer range.

3、 Different power performance

Gasoline engines have higher RPM and more agile power response, making them suitable for scenarios that require frequent acceleration and pursuit of driving pleasure, such as family sedans, sports cars, etc. Diesel engines have greater torque and strong low-speed power, making them more suitable for heavy loads, traction, and other working conditions. They are commonly used in trucks, off-road vehicles, construction vehicles, etc.

4、 Emissions and Environmental Protection

Gasoline engines emit more carbon monoxide and hydrocarbons, but less nitrogen oxides and particulate matter; Diesel engines, on the other hand, have higher emissions of nitrogen oxides and particulate matter. However, with technological upgrades such as the installation of DPF (particulate matter filter) and SCR (selective catalytic reduction system) in diesel vehicles, their environmental friendliness has greatly improved.

5、 Applicable scenarios

Gasoline engines are widely used in household cars, small SUVs, sports cars, etc; Diesel engines dominate in fields such as commercial trucks, pickups, large SUVs, and construction machinery.