Fuel consumption overview

Manufacturers pay close attention to the fuel consumption ratio as they are constantly trying to reduce excess intake of fuel in the combustion chamber. Consequently, most manufacturers are moving from carburetors to injectors because injectors have a good fuel economy.

Fuel consumption is the amount of fuel used per distance (l/100km). Though the fuel consumption rate is particular to the vehicle used, the higher the engine size, the higher the fuel intake. For example, you cannot compare the consumption rate of a 1.4 engine-sized vehicle with 1.6 or 1.8 engine-sized vehicles.

A 1.4 engine-sized vehicle would use up less fuel than the other two options listed above, under normal consumption rates. For the 1.6 engine, compared to the 1. engine, there is a slight increase in consumption rate under normal circumstances. As the sizes increase, so does the consumption rate.

A high fuel consumption rate is called excess intake. The fuel consumption ratio is vital because many things are involved in constantly improving its rate.

Fuel economy, on the other hand, is the distance traveled per one unit of fuel. In other words, it is the inverse of fuel consumption. These two metrics are calculated for each vehicle model through standardized testing procedures and drive cycles. A vehicle's fuel consumption rate is based primarily on its engine, transmission, and drivetrain technology and size.

What affects the fuel consumption rate in a car?

Fuel consumption rate

Many factors affect the fuel consumption rate of a vehicle. The biggest factor is most usually the driver. Driving style can turn even the most fuel-efficient vehicles into embarrassments.Other variables include:

1. Displacement: This is the volume of air your engine can consume in a single revolution, and the more air an engine moves, the more fuel it can consume with every turn.
2. Weight: The heavier the vehicle's load is bearing, the higher the fuel is pulled by the engine to spur it into motion.
3. Gearing: With fewer gear changes available, you will consume a higher volume of fuel.
4. Aerodynamics: The vehicles' engines with the vertical surface area on the front, like trucks and SUVs, must work harder, and use more fuel, to push the air out of the way.
5. Intake and Exhaust Restrictions: More resistance in intake and exhaust means more work and, in turn, more fuel consumption.
6. Mechanical Resistance: Mechanical resistance describes the amount of effort it takes to move each piece of the vehicle's drivetrain. This factor increases fuel consumption, too, as it usually takes away about 15 percent of the engine's power.
7. Altitude: This may be an odd addition, but there is less oxygen that a vehicle can take in at higher altitudes. This notion means it will produce less power, and when this continues, it directly implies that the car would consume more fuel as the driver presses down on the accelerator.
8. Temperature: Just like with altitude, in hotter climates, less oxygen is taken, which leads to less production of power, which causes an increase in fuel consumption.

What causes high consumption of fuel in a car?

This section deals more with what causes a vehicle to develop a high fuel consumption rate (poor fuel economy). It is good to note that the fuel pump does not cause an increase in fuel consumption rate. It only sends fuel to the combustion chamber (the intake base). Various components lead to high fuel consumption rates in a vehicle. Sometimes the fault is in the mechanical block, and other times, it is not.

• Bad air-fuel ratio sensor:

A primary cause of high fuel consumption is a problem with your car's air/fuel ratio sensor. The air-fuel ratio sensor measures the oxygen content during combustion and is sometimes called the oxygen sensor. If the sensor is faulty, it can't accurately gauge and regulate the volume of fuel that goes into the combustion chamber, hence increasing fuel consumption.

• Size of the exhaust:

The size of the exhaust influences the rate of fuel consumption. A very wide exhaust will use up more fuel than normal. This is because the wider the exhaust, the bigger the intake into the chambers. So, you may want to think twice about fitting a larger exhaust.

• Bad fuel injectors:

A bad fuel injector is commonplace when the filter inside the fuel injector clogs with dirt, causing fuel to flow less through the fuel injectors. In turn, this forces the ECU of vehicles to inject more fuel, which trims down the fuel mileage of the car.

Cleaning the fuel injectors at steady intervals would help ease this. Ultimately, it will need to be changed if the fault persists after cleaning. You should see our article on the best fuel injector or cleaning kit available.

• A poorly regulating ECU:

The ECU is the Engine Control Unit, and when it is not regulating properly, it can lead to excess consumption. Due to programming, the ECU has a minimum amount of fuel to go into each of the cylinders. It also handles the distribution of fuel through the nozzles.

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• Stress on the engine:

Suppose a cylinder is not working and one is trying to move the vehicle. In that case, the vehicle ends up getting moved by force, and this process of forcefully moving the vehicle sends too much fuel into the combustion chamber that the vehicle cannot regulate. Pumping in a lot of fuel into a car's engine that is not moving will cause a high consumption rate.

• Incomplete combustion:

Incomplete combustion occurs in a vehicle when the fuel that is supposed to be burned out by the A/F sensor is not burning completely. A sure sign of this is the release of black smoke from the exhaust pipe. With diagnostics tools, you can scan the car to find the faulty sensors.

• Weight:

The more the load on the engine, the more fuel the engine takes to pull that load. Load is like a resistance, and the engine forces its way to overcome that resistance, so when it exceeds the maximum amount of load, you will require more fuel than usual to move the vehicle.Petrol engines, specifically, when one neglects to replace worn-out spark plugs, air filters, or fuel filters, will almost definitely increase.

Other causes include:

• Worn out piston rings and valve.
• Not driving at moderate speed (Driving style).
• Misaligned wheels.
• Road and weather conditions.
• Tire size, thread, pressure.
• Driving with the AC "ON."
• Bad Oxygen Sensors.
• Excessive Idling.
• Dragging Brakes.
• Low Coolant.
• Wrong Oil Viscosity.

How can fuel consumption be reduced?

You can not reduce a normal consumption rate. There had been trials - without success - during the time of carburetors. However, during this time of the injectors, the manufacturers set a minimum intake level for the vehicle to function. A certain volume of fuel can open up the nozzle at the nozzle base.

If that volume is less than it requires, the car will not pull. In this case, there is insufficient intake to accelerate. You cannot do anything to reduce the minimum intake of fuel. You will hinder the proper functioning of the car if you do.

When you notice your car is consuming fuel at a high rate, one of the first things is to get that car to a nearby mechanic for a proper scan and diagnosis. This scan would enable them to check whether any of the sensors have issues.

‍Note: If there is leakage - another cause of high fuel consumption rate - you can easily know from seeing droplets under the vehicle. This case is entirely different from when the fuel enters the combustion chamber, and problems with other components lead to an increased consumption rate.Some tips on reducing high fuel consumption rate:

• Accelerate slowly and do not immediately floor the pedal.
• Get rid of unnecessary things in the car.
• Pay attention to your car tires.
• Get the vehicle services on a schedule.

Key takeaways from our Expert.

• One of the best ways to reduce fuel consumption by your vehicle is to purchase and drive cars with very good gas mileage. Several car brands produce such cars for varying purposes.
• It would be best if you went for smaller engine size, maybe 1.2 or 1.4. This is often the wiser choice, especially if you have no interest in long-distance travel.
• When you notice a high fuel consumption rate, the first step is to scan your car to ensure that all cylinders and sensors function properly. Check your exhaust pipe to know if your engine components are having problems.
• Know the engine size when you are buying a car. The bigger the exhaust, the wider the intake.
• Inspect and maintain your vehicle's tires to avoid hazards and spikes in the fuel consumption ratio.
• Lastly, driving, only when needed, is also a great way to reduce gasoline consumption. Pay attention to the quality of fuel you feed your vehicle.

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