Petrol or Diesel Car: Which is Better?

Every car lover who plans to purchase a car asks a question: “Which car is better: diesel or petrol?”. It is difficult to find an unequivocal answer, since the choice of a particular car depends on many factors: the type of car body, its significance, the area where the machine will be used, etc.

Engines of any type have their advantages and disadvantages, so take the choice seriously, because the engine fuel consumption depends on it, its acceleration to 100 km / h, maximum speed and other important characteristics.

Petrol or Diesel

The working principle of motors

Both diesel and petrol cars belong to internal combustion engines.

In a gasoline engine, the air-fuel mixture is formed in the intake manifold, i.e., outside the cylinder. At the end of the compression stroke, gasoline and air vapors are mixed. This homogeneous mixture is evenly distributed throughout the volume. The result of compression is an increase in the temperature of the mixture to 500 ° C – this indicator is lower than the ignition temperature of gasoline. Sparks are given by spark plugs – the mixture lights up.

In the cylinder of a diesel engine, only air is compressed at a pressure of 30-50 bar. As a result of compression, the air temperature rises to 900° C. At the same time, diesel fuel is sprayed in the combustion chamber in front of the top dead center of the piston. Small drops of liquid evaporate, a fuel-air mixture is formed, which is called heterogeneous – it spontaneously ignites and burns.

Engine efficiency and power

Combustion in a diesel engine is more efficient. This is possible due to the high compression ratio: 20 units for diesel versus 10 units for gasoline. Efficiency of a diesel engine is 40% higher, and fuel consumption is 20% less. The gasoline unit is characterized by greater power.


Due to the high pressure during fuel combustion, diesel engines create more noise and vibration, but high-quality soundproofing cars save the situation.


An internal combustion engine in a diesel car is more environment-friendly. Modern units fully comply with Euro-4 standards and are equipped with a particulate filter, which minimizes the impact on the environment.


The difference between diesel and petrol fuels is as follows: diesel evaporates more slowly, which reduces the likelihood of fire. In addition, diesel units do not use the ignition system.


Theoretically, a diesel engine is more durable due to the rigid and durable cylinder block, crankshaft, elements of the cylinder-piston group, cylinder head. However, this characteristic directly depends on the quality of diesel fuel. From this point of view, the gasoline unit is less whimsical and more resistant to low quality fuel.

A diesel engine, unlike its gasoline counterpart, does not accept low temperatures. At minus 15 ° C, summer diesel fuel thickens and ceases to pass through the fuel filter, as a result of which the car refuses to start. However, the problem has a simple solution – the use of special grades of fuel or the installation of modern heating systems. In addition, diesel engines warm up for a long time, so the cabin will become warm only after 10-15 minutes of heavy traffic. If you live in an area where severe frosts are not rare, give preference to a gasoline plant.

In addition, the diesel engine is not afraid of water since electricity in such engines is used only for starting. That is why SUVs and crossovers are equipped with diesel units.


Owners of cars with diesel engines often have to change filters and oils and check the compression in the cylinders. Such units are distinguished by a complex design, so auto service specialists will not be able to eliminate every breakdown. Repairing a diesel engine is usually more expensive.

Diesel requires large investments, but only if we talk about the short term. If you buy a car for a long time (from 5 years) and plan to drive a minimum of 20 thousand kilometers per year, then due to the low fuel consumption, diesel will save you money.


A diesel engine is more expensive than petrol, however, keep in mind that servicing such a motor will require a large investment.

Diesel or petrol: pros and cons

Petrol engines


  • Low noise level;
  • High power;
  • An opportunity to work at high speeds without consequences for the motor;
  • “Resistance” to low-quality fuel;
  • Spare parts availability;
  • Low cost of service;
  • The ability to tolerate low temperatures.


  • Greater fuel consumption;
  • Less durability;
  • The ability to achieve maximum power in a small rev range.

Diesel engines


  • Cost-effectiveness;
  • Low fuel cost;
  • Lack of ignition system;
  • High torque;
  • Durability;
  • Environmental friendliness;
  • Possibility of contact with water.


  • Large mass;
  • Less power;
  • Low fuel sensitivity;
  • Low frost resistance;
  • High cost of service;
  • Inability to repair in most cases.

As you can see, the advantages of one type of engine are the disadvantages of another. Carefully analyze everything, consider your capabilities, experience, features, procs and cons, and operating conditions. Each manufacturer seeks to minimize the car’s shortcomings, so you can’t say that some type of car looks better. Differences affect some technical characteristics, so you can always choose the option that best suits your capabilities, skills and expectations.

Category: Cars

Tags: driving