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Increased fuel consumption: causes and ways to reduce. Why does fuel consumption increase? Causes and solutions to the problem Why fuel consumption increases

The question in the title is one of the most frequently asked by newbie motorists. However, even experienced car enthusiasts may be quite puzzled by the sudden increase in fuel consumption by the “iron horse”. How much? Yes, because there is no one specific reason why the car’s fuel “appetite” is growing. There are about two dozen of them, and these reasons can be conditionally divided into two subcategories: objective and subjective.

There are ten objective, or independent of the driver, reasons for the increase in fuel. The first is the so-called late ignition. It’s hard to believe, but a shift in the ignition timing by even one degree provokes an increase in engine fuel consumption by 1 percent. And if the angle shifts by more than one degree, the percentage increase in fuel consumption will correspondingly increase. Gaps in . will have the same effect. If violated minimum distance between the central and side electrodes of the spark plug, then the algorithm of their operation is disrupted, which entails an increase in fuel consumption by 4 percent.

Another reason for the increase in the fuel “appetite” of the engine can be... low temperature “”. Yes, yes, if the coolant temperature is lower than expected technical characteristics, this will lead to an increase in consumption by up to 10 percent. This is because the car engine will use more fuel to warm up.

The reasons for the gluttony of the motor can also be various problems in its design. For example, there are cases when fuel consumption increased due to wear of the cylinder-piston group components, crank mechanism or gas distribution mechanism. For example, when the cylinders wear out, the compression in them decreases, the engine power drops, and to restore it you have to add gas more often - so you have excessive fuel consumption.

When the gas distribution mechanism wears out (for example, the toothed belt is pulled out and the toothed pulleys wear out), the engine cylinders lose their tightness and pressure decreases at the beginning of the expansion stroke and at the end of the compression stroke, which again leads to a decrease in engine power. How can I renew it? That’s right, more frequent fuel supply – that’s the increase in fuel “appetite”.

In addition to these breakdowns, contamination (coking) of fuel injectors and driving with an air filter clogged with dirt can lead to increased fuel consumption. In the first case, which occurs due to frequent refueling of low-quality cars, little fuel enters the combustion chamber of the cylinder, therefore, its effective combustion and the generation of sufficient engine energy do not occur.

In the second case, the effect is almost the same, only due to a dirty air filter, a smaller volume of air enters the engine than is necessary for complete combustion of the fuel-air mixture.

The same objective factors for fuel growth include insufficient fuel consumption, wear of the clutch mechanism (which makes it necessary to change the throttle), and incorrectly adjusted wheel alignment angles. It happens that the increased fuel “appetite” of a car is provoked by malfunctions in the sensors of the electronic engine control unit (ECU). For example, incorrect operation of the throttle position sensor will cause the ECU to perceive a false signal that the fuel-air mixture is lean and supply more fuel to the combustion chamber.

Now let's talk about the second subcategory - subjective, that is, directly dependent on the driver. There are fewer reasons here than in the first subcategory, but the effect is the same. The simplest thing that can lead to increased fuel consumption is driving with the windows open. Let's say you are driving a car at a speed of 60 km/h and your windows are open, the wind is blowing through the cabin. Nice? Meanwhile, due to deteriorating aerodynamics, the car has to overcome increased air resistance, and, voila, fuel consumption increases by 4-5 percent.

Case two – car overload. Plus a hundredweight to the maximum vehicle load allowed by the manufacturer (the same applies to installing all kinds of trucks, body kits, spoilers on the car), and fuel consumption increases by 10-40 percent. Solid numbers, right?

The third case is driving “in leaps,” that is, from sharp acceleration to equally sharp braking. With such an aggressive driving style, the “heart” of the car is constantly under stress, which leads to increased fuel consumption. And finally, another common subjective reason is the operation of car electronics (radio tape recorders) or constantly switched on lighting fixtures. Here, fuel consumption can increase from 7 (with the radio constantly running) to 15 (if the air conditioner of your car is constantly running at maximum power) percent.

Knowing about all the reasons that give rise to an enormous fuel “appetite”, you can take certain measures. At least those that will eliminate the subjective factors leading to increased fuel consumption of your car.

The news published a month ago on Motor about the impact of American obesity on fuel efficiency got us thinking: how much does fuel consumption actually increase depending on changes in vehicle weight? We decided to test this using the example of the most popular foreign car in Russia - Hyundai Solaris.

Let us recall the background: American researchers some time ago found out that despite the development of technology and improvements in the efficiency and fuel efficiency of engines internal combustion, any noticeable reduction in fuel consumption on a global scale has not yet been observed. It turns out that the problem lies in the fact that Americans are becoming fatter, and therefore heavier. Experts have found that growth average weight 1 pound (0.45 kilogram) of U.S. vehicle passengers results in a national annual increase of 39 million gallons (147.5 million liters) in fuel consumption! It's a lot.

The weight of a car is a very important characteristic that affects not only the dynamics, but also the “appetite” of any car.

The more the car is loaded, the more gasoline it will use. But the question is: how much more? We decided to look into this.

For our test, we chose the best-selling foreign car in Russia - the Hyundai Solaris sedan, in the most popular modification with a 123-horsepower 1.6 gasoline engine and a four-speed automatic transmission.

We filled the tank “under the plug” using a canister and a “funnel”. Every 100 kilometers, data from the on-board computer was taken, and their correctness was checked by adding fuel from a special measuring container. The amount of gasoline added to the tank made it possible to determine the actual consumption.

Our experiment took place along a test route exactly 100 kilometers long. About half of its distance was federal highways with two lanes in each direction. Another 40 kilometers are “two-lane” local significance with frequent truck overtaking and two railroad crossings along the way. The remaining 20 kilometers had to be driven through two cities near Moscow. The traffic here is quite intense, with frequent braking and acceleration at traffic lights or pedestrian crossings, and sometimes you had to stand in small traffic jams.

During the experiment, the same driver was behind the wheel and drove at a normal pace in compliance with all the rules. traffic and speed limits in force on certain sections of the route. True, in the case of overtaking on the highway, he was allowed to exceed the established speed limit by 20 kilometers per hour to complete the maneuver.

How we calculated the maximum carrying capacity: the curb weight of the Hyundai Solaris (filled car plus driver) is 1198 kilograms, and the total permissible weight is 1565 kilograms. The maximum load capacity is determined by simple subtraction: 1565 – 1198

367 kilograms. To simulate a full load, we used ballast: 75 kilograms each in the remaining four seats (300 kilograms) plus 50 kilograms in the luggage compartment. Another 17 kilograms came from a canister partially filled with gasoline.

In order to avoid the influence of possibly low-quality fuel, the test Solaris during the experiment was refueled with expensive AI-95 gasoline (price - 30 rubles per liter) from a canister. We replenished the fuel in the canister at the same gas station, and even from the same pump.

The test procedure itself is very simple. Four races of 100 kilometers each with different loads: driver only; driver and front passenger; driver and three passengers; driver, four passengers and another 67 kilograms of cargo in the trunk.

Driver only

The average consumption per 100 kilometers exceeded the data declared by the manufacturer by almost two liters (8.4 liters instead of 6.5 liters in the combined cycle).

The dynamics of the Hyundai Solaris with one driver at the wheel (75 kilograms, that’s how much the driver weighs in official factory tests) is quite decent. And it would be even better if not for the simple four-speed automatic transmission. It does not shine with its rate of fire, and when overtaking it often drops right down to the second stage. Our Solaris loses one and a half seconds to a car with a “handle” in acceleration to 100 kilometers per hour!

Driver and one passenger

Average consumption per 100 kilometers increased by 0.3 liters to 8.7 liters and exceeded the data declared by the manufacturer by 2.2 liters.

The presence of an additional passenger, it seems, had no effect on the dynamics or handling of the Hyundai Solaris. Very quiet but confident acceleration in most speed ranges. Overtaking is still easy for the Solaris.

Driver and three passengers

Average consumption per 100 kilometers increased to 9.5 liters (plus 1.1 liters compared to an empty car) and exceeded the data declared by the manufacturer by a third.

The character of the car has changed. Even a partially loaded Solaris accelerates lazily. “Automatic” is forced to use lower levels more often. The engine sounds more strained. The presence of three “passengers” in the cabin aggravated the rocking (although no breakdowns occurred), “smeared” feedback on the steering wheel and noticeably increased roll. In addition, the heavy car began to brake worse.

Driver, four passengers and 67 kilograms of cargo

Average consumption per 100 kilometers increased to 10.3 liters (+1.9 liters) and exceeded the data declared by the manufacturer by 3.8 liters.

The Solaris has difficulty coping with five passengers and cargo in the luggage compartment. The sound of the engine, which was unpleasant even when light, was replaced by a tedious hum. A fully loaded car accelerates quite reluctantly, and gears begin to shift jerkily. I don’t want to drive such a car anymore, and it won’t be possible. Need I say that the loaded Solaris became completely reluctant to slow down?

It is better not to trust the manufacturer's fuel consumption data. It turned out to be impossible to repeat the “passport” results in Russia even on the highway.

Having checked the accuracy of the on-board computer readings by adding gasoline from a measuring container, we were surprised: actual consumption rarely differed by more than 100 milliliters per 100 kilometers. In ordinary life, this error can be neglected.

What's the result? A noticeable increase in fuel consumption when loading the machine. But one passenger has a negligible effect on fuel efficiency - the difference is only 0.3 liters of gasoline per 100 kilometers. This is an extra 60 liters per year with a mileage of 20 thousand kilometers, or nine additional rubles for every hundred kilometers.

However, when fully loaded, fuel consumption increases much more noticeably.

With three passengers on board, Hyundai Solaris already consumes 1.1 liters of gasoline more than with one driver - this means that for every 100 kilometers you will have to spend an additional 33 rubles. And with an annual mileage of 20,000 kilometers, the increase in gasoline costs will be 6,600 rubles - more than 200 “extra” liters of fuel, almost a liter for every extra kilogram of weight!

Along with our experiment with different vehicle loads, we conducted another one: we drove 100 kilometers with two passengers in urban conditions, with traffic jams, traffic lights stopping and starting, and frequent use of the first gear of an automatic transmission. The result of 14.3 liters can hardly be called adequate for a car with an engine capacity of only 1.6 liters. But these are Moscow realities.

Reducing the vehicle's weight by just 45 kilograms will reduce fuel consumption by two percent. Or drive an extra half a kilometer on every liter of fuel.

As for the full load, it is better to drive such a car only in case of emergency. Fuel consumption increases by a quarter – up to 10.3 liters, and annual consumption fuel increases by 400 liters of gasoline! This means that, for example, from Moscow to the beaches of the Krasnodar Territory (3,000 kilometers round trip) you will have to spend at least 1,710 rubles more than when traveling alone. And all this in a car with the dynamics of a turtle, the handling of an elephant and the brakes of an ancient truck. Plus, the overall driving pleasure of the trip, or rather, its complete lack, which is difficult to measure in monetary terms.

4-st. automatic transmission

High fuel consumption is one of the most common complaints of a huge number of motorists using different brands of vehicles. In the context of constantly rising prices for gasoline and other types of fuel, this problem directly affects the family budget and constitutes the main item of expenditure on car maintenance.

1 Why is gasoline consumption increasing?

The reasons for high fuel consumption, as a rule, may lie in several main factors. Various malfunctions of the engine of a technical nature come to the fore - it is the improper functioning of the “heart of the machine” that leads to an increase in fuel costs. Also, often the basis for this phenomenon can be excessive load from additional components of the vehicle - many experienced drivers know that turning on the car air conditioner entails high fuel consumption. Another common factor that can lead to excess gasoline consumption is poor driving habits.

Among the technical problems that lead to increased fuel costs, the most common are the following:

Malfunction of the electronic engine control system;

Incorrect operation of injectors;

Clogged filters - both air and fuel;

- “Jumping” pressure in the fuel system;

Incorrect operation of the automatic transmission;

Malfunctions in the operation of the radiator system leading to engine overheating.

2 Poor performance of ESU and injectors

Most modern cars are equipped with sensors that monitor a number of key processes in the operation of the car's engine. All of them are connected to an electronic control system (ECS), which regulates fuel consumption and other aspects. Its incorrect operation or malfunction of the sensors leads, one way or another, to disruption of the formation of the fuel mixture before it is supplied to the engine cylinders. An incorrectly composed fuel mixture leads to a drop in power and increased fuel consumption. Therefore, with such a problem, you should carry out a complete engine diagnostics to find various hidden problems.

The injector is one of the main components of the proper functioning of the “heart of the car”. Therefore, it is necessary to monitor its condition especially carefully - regularly clean it from dirt and soot and carry out preventive inspections. Contamination on the injectors leads to incorrect combustion of the mixture in the cylinder, resulting in high fuel consumption. In addition, poor performance of this engine component leads to a deterioration in the dynamic qualities of the car and overloads when shifting gears. The latter factor also contributes to an increase in gasoline consumption.

3 Problems with filters

Clogged filters are a real scourge for motorists, especially in dry, dusty areas. Poor air filter flow triggers a cascade of problems that collectively reduce engine efficiency and increase fuel consumption. A low amount of oxygen in the air reduces the efficiency of combustion of the mixture, which causes overload of all vehicle systems, and this leads to big problem. In addition, under such conditions problems begin with the operation of the sensors, which leads to incorrect interpretation of the data by the electronic control system. This also does not contribute to engine efficiency.

4 The reason for the car’s “gluttony” is fuel pressure and incorrect operation of the automatic transmission

Optimal operation of a machine depends on the level of pressure in its fuel system. If it tends to increase or decrease, then due to various mechanisms this becomes the cause of inadequate fuel consumption. With increased pressure when injecting the mixture, it is enriched with an additional volume of gasoline, which leads to its large loss. In the case of low pressure, due to the operation of the ESU sensors, the engine operates longer at higher speeds (to compensate for power), which is also manifested by higher fuel consumption.

The operation of the automatic transmission is largely decisive for gas mileage and other vehicle performance. Therefore, if the automatic transmission is not operating correctly, the first signs are often an unreasonable “roar” of the engine (which indicates its overload) and a subsequent increase in gasoline consumption. Based on this, at the first signs of malfunctions in the automatic transmission, you should most likely contact service center for diagnostics.

5 How does engine overheating affect fuel consumption?

Why does a car radiator cool the engine? What reasons could there be? It would seem, what does it have to do with the fuel system? It turns out that it’s big - it maintains the normal operating temperature of the cylinders (90-100 degrees). At high temperatures, the mixture becomes depleted of fuel due to its rapid evaporation. This leads to a “vicious circle” - detonation combustion of the hot mixture leads to even greater heating of the engine.

In this case, the operation of the ESU sensors is disrupted, the pressure in the fuel system changes, which is the reason for high gasoline consumption when traveling. Therefore, you should carefully check all the cooling components of the car - the radiator’s permeability to liquid, the operation of the fan. After all, a problem with this engine component leads not only to high fuel costs, but also to wear and tear of most machine components.

6 Is it worth saving on air conditioning in your car?

It's no secret that fuel in a car is a large source of energy not only for movement, but also for the operation of a number of additional components. The most wasteful of them is considered to be air conditioning, which is usually where all the additional costs of gasoline are written off. Has your gas mileage increased in the summer? This is fine. However, the share of energy consumption by this product depends primarily on the operating mode of the engine.

For example, when the car is idling for a long time (which is most common during city travel during rush hour), approximately 10-20% of the fuel consumption actually goes to the air conditioning. But with stable engine operation at medium and high speeds, as when driving on the highway, the share of air conditioning in the total cost does not exceed a couple of percent.

7 Correct driving is the key to saving fuel

Often, high fuel consumption is a consequence of driver inexperience. Or if the driver likes to “drift” and often overtakes, then one should not be surprised that fuel consumption has increased. If the purpose of driving a car is not high gas mileage, then you can learn to save money while driving your car.

First of all, you should get into the habit of switching to a higher gear as quickly as possible (depending on the circumstances) - it is the transition moments that absorb the most fuel, and increased consumption results. Also, in some cases, a significant part of the path before stopping can be passed by inertia - the car has a significant mass, so it can travel a fairly long distance in this mode. All these measures will easily eliminate the causes of high gasoline costs.

There is no driver who has never thought about the fuel consumption of his car. Believe me, friends, even owners of expensive supercars also think about fuel consumption. Here's the thing. Most often, increased fuel consumption can be a specific sign of a malfunction in the car. Unfortunately, this search for faults that may have caused increased fuel consumption can be very lengthy and not so simple.

If the fuel consumption (overconsumption) of a car on the same route, with the same driving style by the same driver, has become 50 - 100% more than usual (twice as much), then it’s time to start looking for this reason, why your car started consuming too much fuel.

How to independently determine the cause of increased fuel consumption

Before taking your car to a car service center for diagnostics, to determine the causes of increased fuel consumption, you can independently inspect the car and perhaps you can eliminate the increased fuel consumption yourself.

First, you must initially check the pressure in all tires of the car. The point is that the most common cause Excessive fuel consumption is caused by incorrect tire pressure. For example, if the tire pressure is insufficient, fuel consumption can increase by almost 30%.

Therefore, remember, friends, you must regularly check the pressure in the wheels and never allow the pressure in them to be more or less than 0.5 bar from that recommended by the manufacturer.

Please remember that incorrect tire pressure reduces or increases rolling resistance, which ultimately affects fuel consumption. The formula here is very simple: -The lower the rolling resistance, the lower the fuel consumption.

Air resistance while the car is moving also plays an important role in this factor.

For example, if you installed a box on the roof of the trunk or placed any weight on it, then the air resistance will immediately increase and the car will begin to consume much more fuel.

Among other things, in open areas and when driving at high speed, the vehicle's fuel consumption may also increase, and all this is due to increased air resistance. For example, such a phenomenon (excessive fuel consumption) is often observed when driving along overpasses and on highways. If a strong headwind blows while the car is moving, it can increase by about 10 - 20%.

In particular, an increase in such consumption may also be due to a dirty air filter. Remember, fellow motorists, that a dirty air filter reduces the flow of oxygen that is needed into the engine. As a result, a non-optimal fuel mixture will enter the engine and the fuel efficiency of the power unit will significantly decrease. Therefore, friends, remember, try to check the condition of the air filter not only at those moments when the engine oil is changed, but also inspect the filter between scheduled maintenance intervals.

Mechanical causes of increased fuel consumption

As a rule, all engine components and the attachments cars are directly responsible for its fuel consumption, since they put a certain load on the engine. Any shaft, roller or belt (etc.) must have free movement and not load the engine itself during operation. IN otherwise, during rotation and even slight resistance, you will observe increased fuel consumption by the machine.

Please remember that if something is faulty under the hood of the car, then when you carefully listen to the operation of all systems in the engine compartment, you may hear some kind of grinding, or creaking, or whistling, etc. noises. These sounds will directly indicate to you that some components of the car in the engine compartment are already defective.

In this case, there is a high probability that these car components directly affect the engine load itself, which of course will affect the fuel consumption itself.

The same applies to wheel bearings, which, if worn, will not give the car an optimal ride on the road. Ultimately, the car’s engine will work with increased load, and this will also affect consumption and, naturally, excessive fuel consumption.

The car also plays an important role. If it is not working properly, it can significantly affect the fuel consumption itself. For example, brake calipers may not work simultaneously and synchronously, which will ultimately lead to uneven wear of the brake drum pads.

It is also not uncommon for a problem to occur when one or more wheels overheat much more than the others, and all this is due to a delay in opening the caliper itself after braking the car.

So, dear motorists, remember the following: if your car begins to consume more fuel than usual, then do not forget to check the temperature of the wheel rims after braking (of course, after the trip itself). If one wheel is hotter than the other or others, then there is a problem with the brake system in the car and in this particular wheel, which is also a likely reason for the car’s excessive fuel consumption.

But it will be most convenient to check the brakes directly on the lift, by rotating the wheels and by visually inspecting them. If you suddenly find that one of the brake pads touches the brake disc when the wheel rotates freely, or sticks out too close from the caliper, then you will need a more detailed diagnosis of the brake caliper.

Defects in vehicle attachments and auxiliary equipment can lead to excessive fuel consumption

Malfunction and improper operation of auxiliary equipment installed under the hood of the car can lead to an increase (increase) in fuel consumption. For example, fuel consumption can increase significantly if the same air conditioning compressor malfunctions.

All motorists know that a car consumes very little fuel. But as soon as we turn on the cabin cooling, this fuel consumption immediately increases, from approximately 0.5 to 2.5 liters per 100 km.

This is primarily due to the fact that when the interior cooling is turned on, the air conditioning compressor, which is connected by a clutch and a belt drive to the engine, immediately starts working. As a result, the compressor begins to put a significant load on the engine, and the higher the temperature outside, the more power the air conditioner itself requires to cool the air inside the car.

If this compressor or the clutch itself malfunctions, the engine will constantly be subject to increased load due to excess resistance. Ultimately, instead of 0.5 - 2.5 liters per 100 km in a car with the air conditioning on, it can be twice as much.

The same applies to the operation of the generator, which is also connected to the rotating parts of the motor using rollers and a belt. To operate electrical equipment, a generator is installed in any car. alternating current, which not only charges the battery while the engine is running, but also maintains a certain current strength in the entire electrical circuit of the car.

But as we know and according to the laws of physics, we pay you for this generated electricity with the energy consumed, which is generated in the car due to the combustion of fuel in the engine.

True, with a working generator, the load on the engine is very small. But if the generator in the car is not working properly, then the load on the engine can be immediately increased, which will certainly affect the same efficiency of the car.

Also, a faulty drive roller, or a worn generator belt, or a broken generator bearing can immediately complicate the rhythmic movement of all attachments, which will ultimately increase the load on the engine itself.

So, friends, remember and do not forget to pay attention to the sound from under the hood and, especially at the moment when you start the car engine. If at the moment of startup you hear some noises, then it is likely that there is a malfunction in the drive belts or in the generator itself, which may be the reason for the excessive consumption of fuel by the machine.

Malfunction of electronics and sensors may cause increased fuel consumption

The electronic engine management system can also be one of the main reasons for the increased fuel consumption of the car. If you suddenly begin to notice that your car has begun to consume too much gasoline or diesel fuel, then do not be lazy and be sure to carry out electronic diagnostics of the car.

Diesel engines, with comparable load parameters, initially differ from gasoline engines in lower fuel consumption, as well as better dynamics of traction performance, developing maximum torque at lower speeds. This has contributed to the modern widespread use of diesel engines not only in tractors, trucks and special vehicles, but also in passenger cars. However, in cases where problems arise with increased diesel fuel consumption, the diesel engine loses all its efficiency. What could be the reasons for high fuel consumption and what to do in this case?

Some of the information presented in this article will also be valid for gasoline internal combustion engines. However, taking into account characteristic features design of the diesel workflow system, first of all, it is focused on identifying the causes of overconsumption and ways to save diesel fuel.

The main indicator of the efficiency of any engine is specific fuel consumption. That is, the volume of fuel that is consumed by the equipment in 1 hour with a device power of 1 kW. Diesels are traditionally more economical than gasoline engines.

For diesel engines this value is 200-230 g, and for gasoline power units the same parameter is larger - 265-305 g. These are average values. In addition to them, there are a number of external and internal factors that directly affect the actual performance for a particular technique. Among the main ones are the following:

  • the weight of the tractor or car (the more significant it is, the harder it will be for the motor to spin the transmission mechanism and the more energy will be needed for acceleration);
  • air pressure in tires (reduced - leads to a significant decrease in the level of the coefficient useful action engine);
  • air filter contamination level;
  • long-term idle operation;
  • aggressive driving style with sharp acceleration and deceleration, with excessive engine revs in low gears.

The main and obvious sign of increased diesel fuel consumption during engine operation is a significant difference between the fuel consumption values ​​​​indicated in the documentation for the power unit and the actual values. In addition, high fuel consumption will most often be accompanied by uncharacteristic behavior of the engine during operation.

Signs of increased diesel fuel consumption

This is due to the fact that excess diesel fuel, when it enters the combustion chamber, is not burned efficiently and completely, and this always leads to a loss of power. The engine begins to “choke”, characteristic pops begin to be heard in the exhaust system due to the fact that the fuel begins to “burn out” already there. An additional, very often visible visual sign of increased fuel consumption on a diesel engine is excessive smoke, a very dark or black color of the exhaust gases emitted from the pipe.

The main reasons for increased fuel consumption on diesel engines and the simultaneous appearance of increased smoky exhaust include:

  • The appearance of insufficient tightness of the power supply system.

The tightness of the power supply system for a diesel engine is of particular importance. In particular, air leaks in the inlet part of the system (from the fuel tank to the fuel priming pump) leads to malfunction of the fuel supply equipment. And the broken seal of the part of the system that is under pressure (from the fuel priming pump to the injectors) causes leakage and significant excess fuel consumption. A leak in the power system often occurs due to a violation of the tightness of the connections, due to natural wear or mechanical damage. Violations in the tightness of fuel line connections high pressure determined by the small output of diesel fuel in the places where the tubes are attached to the pump fittings and injectors when the engine is running.

  • Clogged air and/or fuel filters.

This is a very common reason for increased fuel consumption on a diesel engine, which perhaps should even be placed first on the list of the main reasons for excessive consumption. Filters become clogged more quickly with regular use of equipment on dirt or gravel roads and off-road; when periodically using diesel fuel of questionable quality, with foreign impurities. However, the polluted air of especially busy roads in the cramped state of modern megacities also has a detrimental effect on the condition of air filters.

  • Clogged fuel drain line.

If the fuel drain line (from the pump to the fuel tank) is clogged or deformed, this will also negatively affect diesel fuel consumption.

  • Contamination or wear of injectors.

This is already more serious problem, requiring repair or replacement of injectors with new ones. When using low-quality fuel, these rather demanding devices become clogged very quickly, which leads to their damage in the future.

  • Violation of the fuel injection advance angle depending on the rotation speed.

The amount of working fluid in the combustion chamber of the engine and its temperature depend on the rotational speed of the crankshaft - the speed of movement of the piston in the engine cylinder. As the crankshaft rotation speed increases, the absolute durations of ignition delays (in milliseconds) are reduced, but the relative durations in degrees of crankshaft rotation increase. We must not forget about such a moment as injection delay (the time between the start of fuel supply by the pump and the injection of fuel by the nozzle into the combustion chamber). The higher the crankshaft speed, the earlier fuel needs to be injected into the combustion chamber, and vice versa.

  • Large gaps in the valve mechanism.

Correct clearances in the valve group are a necessary element that ensures the correct operation of the entire gas distribution mechanism of the engine as a whole. The size of thermal gaps can be 0.08...0.45 mm, and is standardized for each engine by its manufacturer. After the diesel engine has warmed up, all its operating parts are, to one degree or another, subject to thermal expansion, which depends both on the degree of heating and on the size of the parts, and on the coefficient of thermal expansion of the metal from which these parts are made. Most engine parts expand quite strongly, as they have a fairly serious coefficient of linear deformation of the metal from which they are made.

  • Severe wear of the crank mechanism, due to which the engine power decreases.

Accordingly, in order to maintain it at the level required for work, the driver or machine operator will use the accelerator pedal more often and more energetically.

  • Contamination of cylinders and piston rings.

In this case, as a rule, thick black smoke comes out of the chimney, plus excessive consumption of diesel fuel.

  • Failure of the injection pump - high pressure fuel pump.
  • Malfunctions in the electronics, leading to the fact that the sensors generate incorrect data, and the on-board computer, accordingly, normalizes the injection with errors.
  • High degree of clutch wear.
  • There is a violation in the regulation of the angle at which fuel injection advances in accordance with the rotation speed.
  • Insufficient engine warm-up.

During the winter season, the coolant temperature drops below the required value, and because of this, the engine itself cannot reach the temperature necessary for full operation. In such a situation, the engine will use more fuel to warm up itself, which will affect the overall diesel consumption by about a ten percent increase.

  • Unbalanced wheel alignment.

When the wheels are at different angles and in different directions, this causes much more resistance when driving and, accordingly, increases fuel consumption. Normal fuel consumption returns after the wheel alignment is adjusted.

  • Aerodynamic obstacles of various kinds.

It could be anything that somehow causes increased resistance when driving. In particular, non-compliant tires, luggage racks and boxes, etc.

  • Automatic gearbox.

The use of an automatic transmission is always and in any case fraught with increased fuel consumption compared to traditional “mechanics”.

In addition to the indicated high consumption and increased smoke, most of the above reasons can also lead to a deterioration in acceleration dynamics; to unstable operation of the power unit at idle; to certain problems with its launch.

  • Do not forget about the particularly high demands of modern diesel engines on fuel quality.

Imported diesel engines have previously been very picky about the quality of diesel fuel. And now, with the widespread adoption of the Common Rail electronic injection system, even more so. In this regard, it is necessary to refuel only at well-known gas stations of proven and tested fuel suppliers. If there is a need to refuel at an unfamiliar gas station, then it is advisable to use special additives in this case.

A diesel engine is structurally more complex than a gasoline engine. Mixture formation and injection here are carried out using a fuel injection pump - a high-pressure fuel pump equipped with an electronic control system. With considerable age and operational wear of equipment, especially heavy, heavy-duty equipment, tuning is especially important, since natural imbalances arise; increasing gaps that reduce the quality of the mixture; violation of the injection advance angle.

In particular, the injection advance angle has different optimal values ​​at different speeds: 3° – 800 rpm. (idling), 4° - 1000 rpm, 5° - 1500 rpm, etc. It depends on the diesel fuel pressure inside the fuel pump housing and on the wear of the wave profile of the special washer. To achieve optimal values, a piston (or so-called “timer”) is provided in the fuel injection pump housing, which, by means of a driver, rotates the washer and thereby sets the time for the start of fuel supply to the injector. Timely replacement of a worn washer often solves the problem with fuel consumption and excessive fuel consumption. In addition, timely adjustment of the cyclic supply, which must correspond to the volume of incoming air, will significantly affect diesel savings.

  • Fans of a sharp and aggressive driving style should reconsider their habits, abandoning sharp “gas” with rapid power gains and braking.

It is better to adhere to a smooth and stable style of operating equipment that is optimal for economical fuel consumption. The diesel engine speed indicators should be within 1600-2000 rpm. It also makes sense to avoid upshifting when accelerating to high speeds.

  • Change clogged consumables - fuel and air filters - in a timely manner, avoiding a significant reduction in their throughput.
  • Choose the optimal one for diesel engines engine oil with low viscosity indicators. You should not skimp on oil: you need to replace it within the period established by the manufacturers, and this replacement must be carried out in full accordance with the technical parameters of the tractor or car.
  • Do not forget to regularly monitor the tire pressure level, inflating them as necessary to the specified values.

So, in most cases, increased diesel engine consumption is the first serious signal that there is a malfunction in the tractor or truck. It is necessary to identify this malfunction and eliminate it, if possible, in a short time, without putting these actions on the back burner.