# How to calculate fuel consumption per 100 km? Calculation examples

Many car owners do not know how tocalculate fuel consumption per 100 km. Consequently, they do not know how much their car consumes gasoline or diesel fuel. What is written in the technical specifications is often not true, and if the parameters indicate a consumption of about 8 liters per 100 km, this does not mean that the car consumes so much gasoline. And in general, on cars VAZ the fuel expense can be what you like. In principle, this applies to any machines, because in many respects this parameter is determined by the style of driving, the quality of fuel and even the oil used. The fact is that some oils are able to reduce the frictional force between the engine parts, which causes the consumption of gasoline to drop, but this is not the case now.

## How to calculate fuel consumption per 100 km?

In fact, everything is simple. No complicated formulas are needed. You will only need a calculator. The bottom line is to track the distance traveled by gasoline from refueling to refueling. So, we proceed as follows:

- Do not refuel until the "gas station" sensor on the dashboard lights up. Usually this means that about 10 liters of gasoline remains in the tank.
- Now we go to the nearest gas station and fill up a full tank of fuel. Be sure to fill in the gasoline required by the car manufacturer. In technical specifications this is indicated.
- We get a check at the gas station and see how much fuel we have been fueled. Write down this value or just save the check. Now reset the mileage counter.
- We go on business. We need to spend fuel until the "refueling" light comes on again.

Now that we have spent all the gasoline, we can calculate the real fuel consumption of the car. We have all the necessary parameters. The formula for fuel consumption will be as follows:

Consumption = X * 100 / Y.

In this formula:

- X - the volume of fuel. It is indicated in the check.
- Y - distance traveled, which you see in front of you on the dashboard (if you remember, at refueling we dropped the mileage counter).

For simplicity, we give a simple example. Suppose, after the lightning of the bulb "gas station" we refilled 40 liters of fuel. We reset the mileage counter, drove on business and again saw the "gas station" light bulb. Now we look at the counter and see that we, for example, drove 500 kilometers. This means that for 500 kilometers, 40 liters of gasoline is spent. If 500 divided by 40, then we get a gas mileage of 1 kilometer. In this case, there will be 0.08 liters per kilometer. But we need to know how to calculate fuel consumption per 100 km, which means that the obtained value should be multiplied by 100. As a result, 8 liters will be produced - this is how much the car will consume gasoline in this example.

## The second method of calculation

You can also do it in another way. When the "gas station" light comes on, it is necessary to charge exactly 10 liters of fuel and drive until the "gas station" starts flashing again. After the blinking starts, look at the distance traveled. If the meter shows 80 km, for example, the calculation will be as follows:

10/80 * 100 = 12.5.

This means that the engine consumes 12.5 liters per 100 kilometers.

## Errors in calculation

Naturally, such a calculation is veryrough, but it gives an approximately correct idea of fuel consumption by car. After all, it's not always necessary to drive in the city, sometimes the driver leaves for the road, and when driving on a flat road and on an increased gear, fuel consumption is reduced. Even in the technical specifications, the consumption of gasoline when driving in a city or along a highway is indicated.

Therefore, it is desirable to calculate the flow twice. The second time such an operation should be done with a trip to the track. Most often it turns out that the city consumption of fuel is reduced by 2 liters.

## Consumption in modern machines

More or less expensive cars have onboardcomputers, which indicates the consumption of gasoline from the moment of the beginning of the traffic to the current one. You can also see the consumption for the entire operation of the machine. Such technologies remove questions about the consumption of gasoline.

However, even in cars without an on-board computerthere are special OBD II connectors. You can connect them to the OBD II adapter, which will transmit information about the state of the car's systems via a Wi-Fi or Bluetooth-interface to the phone or tablet. It indicates engine speed, machine speed, air conditioning pressure, and fuel consumption per 100 km. There is a similar device inexpensive - about 500 rubles, although there are models at a very high price. If you are not satisfied with these methods of checking the flow, then try to purchase an OBD adapter and watch the flow directly from your mobile phone. Such connectors are equipped with almost all cars produced after 1990.

## Conclusion

Now you know how to calculate fuel consumptionon 100 km. The methods suggested above make it possible to understand how much your car is gluttonous. Of course, they will not give exact data on fuel consumption, but you can determine the "appetite" of the engine.