Difference VS Petrol Engine and Diesel Engine

Here’s a comparison of petrol (gasoline) engines and diesel engines, highlighting their key differences:

Feature	Petrol Engine	Diesel Engine
Fuel Type	Uses petrol (gasoline).	Uses diesel fuel.
Ignition Process	Relies on spark plugs to ignite the air-fuel mixture.	Uses compression ignition; fuel ignites due to high pressure and temperature.
Compression Ratio	Lower compression ratio (typically 8:1 to 12:1).	Higher compression ratio (typically 14:1 to 25:1).
Efficiency	Generally lower thermal efficiency.	Generally higher thermal efficiency, leading to better fuel economy.
Power Output	Produces more power at higher RPMs.	Produces more torque at lower RPMs, making it better for heavy loads.
Engine Design	Typically lighter and more compact.	Generally heavier due to stronger components to withstand higher pressures.
Emissions	Produces more carbon monoxide and hydrocarbons.	Produces more nitrogen oxides (NOx) and particulates.
Cold Weather Performance	Better cold starting performance.	Can have difficulty starting in very cold weather without additives or glow plugs.
Maintenance Costs	Generally lower maintenance costs; parts like spark plugs need regular replacement.	Typically higher maintenance costs; requires more durable components and regular servicing of fuel injectors.
Applications	Commonly used in cars, motorcycles, and light vehicles.	Widely used in trucks, buses, heavy equipment, and some cars (especially in Europe).

This table summarizes the major differences between petrol and diesel engines, reflecting their unique characteristics and applications in various vehicles.