Kia error causes rich mixture. Lean or rich mixture of gasoline and air. How does error P0172 manifest itself?

Perhaps the most important feature electronic fuel injection systems - this is the presence feedback according to the composition of the air-fuel mixture. Using a lambda probe, the engine control unit will determine at any time whether the mixture is rich or lean (if a narrow-band oxygen sensor is used). Or even find out exactly the composition of the mixture (when installing a broadband sensor).

Rich - lean mixture

Next, the closed loop algorithm comes into effect (in English terminology – closed loop). By constantly analyzing the signal from the oxygen sensor, the controller changes the composition of the fuel mixture every time the sensor voltage crosses the threshold corresponding to the stoichiometric mixture (ideal fuel/oxygen ratio). Therefore, when the engine is running, the voltage at the output of the lambda probe has a form close to a sinusoid.

As soon as the voltage rises (the mixture turns from lean to rich), the controller, after waiting some time, begins to gradually reduce the injection time, making the mixture leaner. This continues until the voltage at the oxygen sensor drops, indicating that the mixture has become lean. Further, the injection time increases again - that’s why the algorithm is called a “closed loop”.

Since, as the vehicle is used, real operating parameters may seriously deviate from the ideal ones specified by the firmware, a long-term correction parameter for the mixture composition is used. It is set by a self-learning algorithm; its operation can be explained “on the fly” as follows: if for a long time the short-term correction (set by the lambda probe) deviates significantly from zero, then the average value of the deviation is taken into account when calculating the opening time of the injectors even before applying the short-term correction.

For example, our faulty fuel pressure regulator overestimates the amount of fuel that actually enters the cylinders at the estimated opening time of the injectors. Accordingly, the moment of transition from a lean to a rich mixture via the lambda probe will take place with a negative value of the short-term correction: the mixture will have to be leaner constantly. The self-learning algorithm will remember this negative correction.

Thus, even with serious deviations in data from the sensors and the actual state of the engine, the injection system maintains the specified mixture composition. However, any correction has its limits, and when the correction parameters go beyond the limit values, the indicator will light up Check Engine.

Causes and symptoms of error P0172

As soon as the correction parameters (usually displayed as percentages in diagnostic programs) fall below a specified threshold (for example, -70%), an error with OBD-II code P0172 is automatically recorded. To understand the reasons for the occurrence of such an error, you need to know that the composition of the ECU mixture itself is unknown; it is based solely on the voltage at the output of the lambda probe.

Dirty lambda probe

Therefore, the first reason that can cause error P0172 is simple contamination of the lambda probe measuring element with soot. In this case, even with a very lean mixture, oxygen from the exhaust gases does not penetrate through the carbon deposits to the lambda probe, and the output will always have a signal corresponding to a rich mixture. Accordingly, the injection ECU will reduce the fuel correction parameter until it starts to go off scale. For the algorithm, this will cause the P0172 error to be indicated.

Without diagnosis, the symptoms are obvious. Cold engine it starts normally or slightly with difficulty (since the “closed loop” algorithm is turned off during start-up mode and during warm-up), then the stability of the engine deteriorates and the machine stalls under load. The candles are covered with white soot or even have signs of overheating (the combustion temperature of lean mixtures is higher). During diagnostics, there is no “sinusoid” at the output of the lambda probe, the voltage does not change even in forced idle modes, when the fuel supply is turned off, and the oxygen sensor would definitely show a lean mixture.

However, the mixture may actually be rich. On cars equipped with a mass air flow sensor, one of the most likely causes is a malfunction of the mass air flow sensor. Over time, these sensors begin to overestimate readings. If for VAZ engines normal flow air on Idling is 9-10 kg/h, then if the sensor is faulty it can be 15 or more. The author has seen a Gazelle that literally flooded the engine with gasoline, because at idle its air consumption was supposedly 90 kg/h. Moreover, the primitive algorithm of the old Mikas did not even consider this a malfunction.

Based on incorrect readings of the mass air flow sensor, the injection computer, when calculating the amount of fuel, over-enriches the mixture, and the “closed loop” algorithm takes the correction to a minus. This is diagnosed “on the spot” by excessive fuel consumption and black spark plugs, and when the mass air flow sensor is turned off, engine performance becomes better.

The injection system sensors may be in good working order, but fuel is still consumed due to mechanical reasons:

• a malfunction of the fuel pressure regulator, which does not dump excess fuel into the return line (modern regulators are built into the fuel pump module and physically there is no return line - the “extra” fuel goes directly into the gas tank);

That is, the ECU calculates the injection time correctly, but in reality, more fuel is supplied to the cylinders than calculated, and the “closed loop” again takes the corrections to a serious disadvantage. It is also possible that the return hose itself may be pinched on older cars with a drain ramp: the regulator would be happy to dump excess fuel into the tank, but it doesn’t work.

All the injectors rarely begin to “flow” at once, so this problem can be distinguished immediately: in one or two cylinders the spark plugs are blacker than in the others. If the overflow occurs due to a malfunction of the pressure regulator, then all the spark plugs will be black. And connecting a pressure gauge to the rail will immediately indicate a faulty fuel pressure regulator.

“Extra” fuel also appears due to a malfunction of the fuel vapor recovery system (in other words, the adsorber). This is easy to check by pinching the hose going from the adsorber to the inlet.

Finally, excess fuel gets into the cylinders and through the crankcase ventilation if gasoline gets into the oil. This can be easily “caught” by an increase in the level, a noticeable “dilution” of the oil, and a characteristic odor.

How to resolve the error

Regardless of the cause of error P0172, you should not delay repairs; a rich mixture will shorten the life of the catalyst. The most likely sources of problems are checked and eliminated first:

1. Examine the candles. Check by the presence of black soot that the mixture is over-rich.
2. On vehicles with a return line, remove the hose from the regulator and try to bleed it to ensure it is not pinched anywhere along the way to the gas tank.
3. Find out the correct fuel pressure values ​​for your car. For a VAZ with a drain ramp it is 3 bar, with a drainless one - 4. Please note that the pressure on the drain ramp is measured with the vacuum pipe removed from the regulator, otherwise the readings at idle will be 0.6-0.5 bar lower! The pressure gauge itself for measurement can be inexpensively purchased or borrowed.
4. Connect the tester to the signal wire of the lambda probe in voltage measurement mode. More convenient to use pointer instruments– they do not have the same inertia as digital ones; on a working lambda probe you can see the needle oscillate from 0.25 to 0.75 V.
5. Measure the voltage at the output of the mass air flow sensor with the engine turned off, comparing it with the standard one, if it is possible to find it out. For example, for VAZ sensors it should not be higher than 1.03 V (Bosch) and 0.04 V (Siemens).
6. Check level and condition motor oil.
7. Without “catching” the source of the problem, contact the service - for a qualified diagnostician there will be no problems here.

Video: P0172 Rich mixture

Seal

Error p0172 on the VAZ 2114 is a fairly common problem that is signaled by the on-board computer. What does this error code mean, what causes it, and what actions should the car owner take? We’ll talk about this in today’s article.

What does error 0172 mean?

Code P0172, which is issued by the on-board computer, is a system error indicating that the fuel mixture is too rich in the combustion cylinders.

An over-enriched mixture is a mixture in which the air content is less than normal, and, on the contrary, there is more gasoline than necessary.

Theoretically, the error can be ignored, but unstable engine operation will not allow you to use the car normally, so you still have to delve into the problem. An average static engine requires 1 kg to operate correctly. about 15 kg of gasoline. air.

If there is less air, then the mixture is considered rich, and if, on the contrary, it is poor. Of course, the proportions of fuel and air are slightly different in different operating modes of the car, so the ECU continuously monitors this ratio and immediately alerts the driver in case of problems.

Signs of a rich mixture on a VAZ-2114

A too rich mixture on a VAZ-2114 manifests itself not only by issuing error p072, but also by the following symptoms:

• • high gas consumption. Moreover, the consumption increases sharply and is explained by the ineffective consumption of the fuel mixture;

• • loss of engine power. A mixture in which the air content is less than normal burns more slowly than usual, and often not completely. As a result, the piston is not provided with optimal force, which is why the engine power decreases;
  • black smoke from the exhaust pipe. The reason lies in the lack of filtration of gas from gasoline combustion;

• the appearance of strong pops in the muffler. The reason is a lack of air in the engine cylinders.

Reasons for a rich mixture on the VAZ-2114

The formation of a rich fuel-air mixture occurs in a number of cases:

• • incorrectly adjusted fuel system. As a rule, this is the result of intervention in the system to reduce gas mileage or increase power;
  • clogging air filter. In this case, the required amount of air does not enter the combustion chamber;

A dirty air filter is the most common reason formation of a rich mixture. If error P0172 is detected, you should first check the condition of the filter.

• • incorrectly configured injectors;

• • high fuel pressure in the rail or malfunction of the pressure regulator;
  • air flow meter failure. In this case, the sensor transmits incorrect data to the on-board computer, as a result of which the fuel supply system operates in accordance with these indicators;

• economizer malfunction.

Ways to eliminate error p0172

If injection engine prepares a mixture that is too rich, the first thing the car owner needs to do is eliminate various additional settings for the volume of air or gasoline supplied.

If the vehicle has been adjusted fuel system, they should be cancelled. If the engine runs for a long time on an over-rich mixture, the result may be damage to the pistons and spark plugs.

Often a rich mixture on a VAZ 2114 is formed due to incorrect supply of gasoline by the injectors. You should pay attention to the injectors if traces of fuel assembly combustion are found on the outside of the injector. Traces from the combustion of the fuel-air mixture can be found on the copper o-ring. If such signs appear, it is advisable to ensure that the injector is installed correctly.

If the problem is in the injectors, then it is not necessary to remove them. To check the functionality, just listen carefully to the noise of the motor in operating condition. Faulty (or clogged) injectors produce a high-frequency, dull sound. Faulty injectors will have to be replaced, but clogged ones can be cleaned at home.

There are several methods for this:

1. Flushing with special additives that should be added to fuel tank. The advantage of this method is that the additive not only flushes the injectors, but also normalizes the operation of the entire engine.
2. Ultrasonic cleaning. This work is not quite simple and requires first removing the injectors from the car and then installing them back. In addition, expensive equipment is needed to carry out such cleaning.
3. Cleaning the injectors using a syringe and a special washing liquid.

If the cause of error p0172 lies in a dirty air filter, then it is best to simply replace it with a new one. If in this moment If you don’t have the money to buy a new filter, you can clean it quickly enough.

Cleaning the air filter

The procedure is very simple:

• open the hood, disconnect the battery and unscrew the screws of the filter safety cover;
• manually remove the filter from the grooves of the cover;
• treat with a special impregnation, wait 10-15 minutes and rinse the filter element in clean water;
• Allow the filter to dry completely and replace it. You can speed up the drying process using a regular home hair dryer.

If the cause of the rich mixture is a faulty pressure regulator, it should be replaced:

• disconnect the negative terminal of the wire from the battery;
• remove the vacuum hose and unscrew the nuts of the drain tube, holding the hose fitting;
• use a rubber ring to connect the washer and tube;
• unfasten the clamping bar;
• loosen the screws that secure the regulator to the ramp and remove it;
• Attach the new regulator in the reverse order.

Conclusion

In this article, we examined in detail the concept of error P0172, which is diagnosed by the on-board computer on the VAZ-2114, the reasons leading to it and ways to eliminate it.

In order for the car to perform well, the engine needs good power. In order for an explosion of the required power to occur in the cylinders, a high-quality air-fuel combustible mixture is required. But sometimes the mixture can be too rich or too lean. What does it mean? What are the reasons for the appearance of rich and lean mixture? You can find the answer to these questions after reading the article below.

What does rich fuel assembly mean?

When the fuel mixture is rich, the ECU generates system error p0172 from the coolant sensor. The appearance of error p0172 does not mean that any of the sensors that control engine operation have failed. This error, like error p0171 (lean mixture), indicates that the parameters of the fuel-air mixture do not meet those specified by the manufacturer. Signs of a rich fuel assembly may be increased consumption fuel, inconsistent speed when the engine is running, choking at idle, smoke from the engine.

Note! A normal combustible mixture is considered to be a mixture with a standard oxygen content (15 kg of air per 1 kg of fuel). At the same time, sufficiently high engine power is developed with good fuel efficiency.

If the air intake drops to 12-13 kg, then gasoline predominates in the mixture, and the mixture will not completely burn in the cylinders. Engine power drops and fuel consumption increases. At the same time, efficiency may drop by 15-20%.

Lean value

A lean fuel mixture will be indicated by error p0171. Signs of a lean fuel-air mixture include a drop in engine power (the car accelerates slowly), idle speed The engine is unstable, the car does not respond well to the gas pedal.

What is a lean mixture, and what happens in this case? With a lean mixture, the amount of air in the cylinders increases significantly and exceeds more than 15 kg of air per 1 kg of gasoline. At the same time, the fuel combustion process becomes worse, and if the indicators exceed more than 22-25 kg of air per 1 kg of fuel, the engine may stop.

Why does a rich mixture appear?

You can find out that your engine has too rich an air-fuel mixture (error p0172) by measuring CO (carbon monoxide) and CH (soot) during a technical inspection or when diagnosing the engine during a scheduled Maintenance. You can find out about the occurrence of a problem during operation if you notice that black smoke is pouring out of the exhaust pipe and the engine is shooting into the muffler.

There may be several reasons for the appearance of a rich air-fuel mixture:

1. In general, an enriched fuel-air mixture is either a lot of gasoline or very little air. Based on this, it is necessary to check the engine systems. The appearance of more gasoline is a more difficult problem to diagnose. One of the simplest solutions is to check the condition of the air filter (if it is dirty, replace it), check the functionality and position of the air and throttle valves in the intake manifold. If the dampers are not fully open, a small amount of air will enter the cylinders, which will lead to an over-enrichment of the mixture. Examine them. If necessary, adjust or reconfigure them. Also pay attention to the condition of the mass air flow sensor or air pressure sensor in the intake manifold.

2. Solving the problem with injectors is more complex and requires appropriate equipment. To check the fuel consumption through a calibrated hole, the completeness of the injector closure (so that it does not leak), the operation of the shut-off switch (so that it does not freeze), the injector is checked on a stand: what pressure it can withstand, how the electromagnetic control unit works. Malfunctions may include incorrect operation pressure reducing valve ramps. Because of this, increased pressure is created in it, which can lead to incorrect operation of the injector. If these problems occur, repair or replacement of the nozzle or components is necessary.

If your car is equipped with a lambda probe, then do not forget to check it, because the signals that adjust the mixture composition depend on the quality of the device.

Why does a lean mixture occur?

The causes of a lean fuel mixture will be the same sensors and engine systems that we discussed above.

Signs of a lean mixture are popping noises in the intake manifold. Popping can occur for the following reasons:

1. Due to the slow combustion of the mixture in the cylinder during the working stroke, the intake valve has time to open during the ventilation stroke of the cylinder, because of this, the ignited fuel mixture is combined with the fuel going into the adjacent cylinder during the intake stroke.

2. Shift in valve timing due to a violation of the timing drive tension adjustment or partial destruction of the timing drive (cutting teeth from the belt).

3. Early ignition. Also, signs of deterioration in the quality of the fuel mixture will be engine overheating (the combustion process lasts longer and heats up a larger number of parts and cylinder areas). Significant reduction in engine power.

To eliminate the “lean mixture” error and the above problems, pay attention to the following reasons:

1. Problems with the intake system.A lean fuel mixture is when there is a lot of air and not enough gasoline. To eliminate these problems, the air supply system must be checked for operation. throttle valve. It should correspond to the position of the gas pedal. When the pedal is released, it should be completely closed, and when the pedal is pressed, it should open smoothly and evenly until the air channel is completely open. If equipped with an automatic choke, please note that its position must correspond to the engine temperature. On a hot (warmed up to operating condition) engine, the air damper must be fully open. On a cold engine, depending on the outside air temperature, it should be turned to a certain degree. If it is in the open position, then your air damper opening control system is faulty. One of the reasons for impoverishment air-fuel mixture There may also be damage to the gaskets on the intake manifold and air leaks. To fix this problem, you need to tighten the intake manifold and, if necessary, change the gaskets. Check the condition of the mass air flow sensor or the air pressure sensor in the intake manifold. Check the condition of the terminal connectors to ensure correct transmission of information to the computer from these sensors.

2. Problems with the fuel system. Here the problems are exactly the opposite when the mixture is too rich. To eliminate these problems, injector testing must be carried out using appropriate equipment. In this case, you should check how much fuel passes through the nozzle. It may be clogged with mechanical impurities that have passed through the filter. In this case, the sprayer or nozzle must be washed. In addition, check the electromagnetic unit: how well and completely it raises the needle.

Attention!Do not forget to make sure that the electronic unit is securely connected to the engine ECU: whether the actuator signals are fully transmitted. You also need to check the work fuel pump(how much fuel it supplies to the rack) and the condition of the pressure reducing valve (does it hold the operating pressure in the rack). If one of the listed problems is detected, the injector or component parts will need to be repaired or replaced.

3. Problems with the condition of the gas distribution mechanism. If you don't regularly check the condition of your car's timing system, problems may arise with one of the main engine systems. To ensure that the timing system does not affect the appearance of a lean mixture, it must be checked and, if necessary, adjusted. If a timing fault is detected, the faulty part must be repaired or replaced. When checking the timing belt, pay attention to the condition of the drive belt tension roller, the absence of delamination, cord bulging, cracking of the belt body, or destruction of teeth. If there is a drive chain on the motor, make sure that good condition chain tensioner and its dampers. At the same time, check whether the chain is stretched. If there are any malfunctions, repair or replace parts.

Did you know? Problems with lean and rich mixture can cause a fire in your car.

First aid for a car [error p0172]

If error P0172 “mixture too rich” appears, first reset the fuel trim to 0%. To perform this operation, you must find a sensor (node) that provides incorrect information. To detect it, use a tester or multimeter. Check the mass air flow sensor, intake manifold air pressure sensor, lambda probe, coolant sensor. Their readings must comply with the manufacturer's instructions. Make sure that the intake and exhaust manifolds are securely fastened and the gaskets underneath them are in good condition.

The P0172 error code is one of the most common that owners of vehicles with electronically controlled. It is often found on cars from the AvtoVAZ plant, as well as on foreign cars - Mercedes, Mazda, Toyota and others. The P0172 code indicates to the driver that the combustion chambers are being supplied with too rich a mixture, causing the engine to malfunction and increasing fuel consumption.

Table of contents:

How does error P0172 manifest itself?

The air-fuel mixture can be over-rich for several reasons, depending on which the behavior of the car will change. So, with error P0172, the car may behave as follows:

• A cold engine will “choke” until it warms up completely;
• The engine will “choke” in a cold and warm state at idle, and the speed will begin to “float”;
• Fuel consumption will increase;
• The car will become less playful.

Symptoms of the P0172 code may occur together or separately from each other.

Under what conditions does P0172 occur?

To the electronic unit control diagnosed error P0172 and transmitted information about it to the driver, he should receive information from a number of sensors. The conditions for displaying a message about over-enrichment of the air-fuel mixture are as follows:

Why does P0172 - mixture too rich occur?

To understand the reasons for the appearance of error P0172, you need to understand the process of formation of the air-fuel mixture and its combustion. After analyzing it, we can conclude that the mixture may be enriched due to the supply of too much fuel or due to insufficient air supply.

Absolute pressure and oxygen sensors are responsible for supplying air for mixing with fuel.

In addition to improper operation of the sensors, an error with lack of air can occur for the following reasons:

• Insufficient compression;
• Malfunctions of the gas distribution mechanism;
• Torn or cracked seals or gaskets;
• Violation of thermal gaps.

Also, error P0172 can manifest itself due to over-richness of the mixture as a result of poor combustion. This problem may be caused by improper operation of the spark plugs or ignition coils.

It cannot be ruled out that problems with the mixture and its combustion arise due to failure of the oxygen or air flow sensors.

What to do if P0172 Combustion Too Rich Occurs

To determine the causes of the error, you need to check the information that the diagnostic scanner transmits when simulating the conditions for the error. If you can’t immediately identify the problem, you need to act according to the following scenario:

After identifying and correcting the malfunction that led to the P0172 error, it is necessary to reset the fuel trim. This is required to reset the long-term adjustment.

Reading time: 6 minutes.

Rich mixture causes injector. A rich mixture is a fuel mixture prepared with an excess amount of gasoline in the engine cylinders (injector). The reasons for the formation of a rich mixture are numerous and can be caused by improper operation of the vehicle, as well as technical malfunctions of the engine systems.

As is known, in modern cars engines installed internal combustion(ICE). This means that it is not gasoline or diesel that burns in the engine cylinders, but a fuel-air mixture. This happens as follows. Fuel supply nozzles spray fuel, which evaporates in front of the incoming valves in the form of a fine suspension. And already in the cylinders the combustion of these vapors, mixed with air from an electric spark, occurs.

Thus, the fuel-air mixture (FA) is a derivative of liquid fuel and fine air with the inclusion of a small amount of the vapor phase.

Rich fuel assembly: concepts

Thus, the composition of the fuel mixture is determined by the ratio of air to fuel. This ratio depends on the volume of liquid fuel supplied to the cylinders. When acceleration occurs, the liquid fuel is intensively saturated with air mass. When this ratio is disrupted, the air/fuel mixture is either rich or lean.

Preparing the fuel-air mixture is a process for which the car's injector is responsible. Injection system injection prepares mixtures with different oxygen contents, and this is what provides a variety of operating modes for the internal combustion engine. It is the composition of the fuel mixture that allows the car to sharply increase speed while overtaking or overcome an incline.

A rich mixture is a mixture that contains less air than required and more gasoline than required. The burning rate of the rich mixture is reduced, and therefore it burns out already in the muffler. Sometimes such a mixture is symbolically called high-calorie.

There is a mathematical formula that determines at what ratio of atmospheric air to fuel the fuel mixture will be normal, rich or lean. It is believed that the normal ratio is a mixture of 14.7 kg of air and 1 kg of liquid fuel. If the ratio of 14:1 is increased in favor of the air mixture, the fuel mixture will be lean. And, on the contrary, when the ratio is 14:1 in favor of liquid fuel, the mixture will be rich.

Artificial boosting of engine power is ensured by adjusting the fuel supply when the amount of supplied oxygen increases. The desire of the car owner to save on fuel consumption is achieved by supplying more atmospheric air.

Poor fuel assembly: concepts

- this is a fuel assembly with a reduced gasoline content and an increased air content.

Error code assigned to this error on-board computer- P0171. Literally, this code stands for very poor fuel supply. Sometimes poor FA is called low-calorie.

A poor fuel mixture shows itself with the following signs: very poor traction, especially noticeable on steep climbs, engine overheating, the injector makes popping sounds, and white or gray smoke comes out of the exhaust pipe.

Reasons for preparing a lean fuel assembly: fuel pump malfunction, use of gasoline with water or other impurities, fuel sensor malfunction, vacuum hoses or intake manifold malfunction, injectors supply too little gasoline, pressure sensor malfunction.

Signs of a rich mixture

The formation of a rich fuel mixture occurs with a chic set of manifestations.

1. The first and most important sign: the malfunction indicator issued by the car’s on-board computer lights up. Error code: P0172.
2. The car muffler makes a loud popping noise. This happens due to a lack of air in the engine cylinders and, as a result, the air burns out already in exhaust pipe.
3. Exhaust gases are black or gray. This occurs due to the fact that the fuel assembly burns not in the engine, but in the exhaust pipe; the exhaust gas does not undergo any purification by filters; when burning in the pipe, the amount of atmospheric air sharply increases.
4. The car is less dynamic, less powerful. This is explained by the slow combustion rate of the fuel mixture. As a result of slow fuel combustion, power failures occur. If the mixture is over-enriched, it is even possible that the car simply will not move.
5. Fuel consumption has increased sharply. It is explained by the inefficiency of using the fuel mixture: it tries to cover the low combustion rate with additional injection of liquid fuel.

Reasons for the formation of a rich mixture

The formation of a rich fuel-air mixture occurs in the following cases:

1. Reasons directly related to incorrect operation and incorrect configuration of vehicle systems:

• as a result of improper adjustment of the fuel system in order to reduce fuel consumption;
• as a result of improper adjustment of the fuel system in order to increase power.

1. Related to malfunctioning engine systems:

• the injectors supply too much fuel;
• air filter contamination;

• the air damper is gaping;
• malfunction of the fuel pressure regulator;
• malfunction of the air flow sensor, malfunction of the gasoline vapor recovery system, incorrect operation of the economizer.

First aid for a car with error P0172

The first thing that should be eliminated if the injector prepares a rich mixture is to abandon all kinds of additional settings for the volume of supplied air or fuel. The vehicle's fuel system may have been adjusted. If this is the case, it is necessary to cancel these adjustments, since prolonged operation of the engine on a rich mixture can lead to breakage of the pistons and failure of the spark plugs.

The second common reason for the formation of a rich mixture is incorrect fuel supply from the injectors. You can suspect injectors if there are traces of fuel assembly combustion on the outside of the injector. Traces of fuel assembly combustion can also be found on one side of the copper O-ring. If such signs are found, you need to check whether the injector is installed correctly and whether the o-ring is in place.

The third undeservedly ignored reason is a dirty air filter. If the filter is heavily clogged, the pressure in the cylinders increases, and as a result, incorrect preparation of fuel assemblies occurs.

The fourth reason for cooking a rich fuel assembly is incomplete closing of the air damper/valve. In this case, the pressure in the cylinders is reduced and this, again, leads to errors in the preparation of fuel assemblies and malfunction internal combustion engine systems: the injectors begin to pour more fuel, increasing consumption and reducing power.

If the fuel pressure regulator does not fully function on its own, then the errors here are the same as in the previous two cases: increased or decreased pressure in the cylinders.

The sixth group of reasons is not so common. Problems with the air flow sensor, the fuel vapor recovery system, or problems with the economizer are often a consequence. However, if all the previous reasons have been eliminated, but the problem remains, you should check this group of reasons. If the problem really lies with them, then it will be solved by simply replacing these parts.

Preparing rich fuel assemblies is a very common problem, and therefore very familiar to mechanics in car service centers and metalwork shops. The problem of preparing bad fuel assemblies is usually eliminated quickly, literally in one or two minutes and for little money (depending on the level service center and car model).

It should be noted that 90% of errors can be solved by simply adjusting the liquid fuel injection. The main thing here is to fix the problem in time, before the injector breaks and other problems arise: for example, pistons may become unusable, spark plugs may burn out, etc.