Most of the most modern cars still run on engines. internal combustion - that is, principles more than 150 years old. Despite all the electronic, intelligent stuffing, engines of all manufacturers are still susceptible to typical ICE diseases and problems. One such problem is the rich fuel mixture, which even modern car with an injection engine may become similar to a self-propelled sidecar of the second half of the 19th century.

Symptoms of this problem are difficult to ignore, and impossible to ignore, regardless of driving experience. If your car engine is running at a rich fuel mixture, you will notice a number of unpleasant signs:

• pops and shots from the silencer;
• black or gray smoke comes out of the exhaust pipe;
• on dashboard the "Check engine" icon is on;
• when reading, error P0172 is detected;
• dips in dynamics - the car seems to stumble;
• fuel consumption increases significantly;
• in advanced cases, the car may not start at all.

Of course, with such problems, the car is almost impossible to operate. Many car owners, especially inexperienced ones, are very scared of these symptoms and consider it a serious breakdown, which will be expensive to fix. In fact, everything is much simpler and more prosaic, and it can be expensive just to ignore the problem of a rich mixture for a long time.

What is a rich blend

The very name of the ICE suggests that fuel is burned inside the engine, in its cylinders. The process of burning something, as we know from the school curriculum, is the combination of molecules of something with oxygen molecules. Therefore, the engine needs a constant supply of air to operate. The problem is that there is only 20% oxygen in the air, and the oxygen molecules themselves are much smaller than gasoline molecules, so for a full combustion you need almost 15 times more airthan the fuel itself.

A rich fuel mixture is formed when this ratio is violated for some reason - more gasoline is supplied than needed. This is not good, because gasoline no longer burns out completely - it simply does not have enough oxygen for this. Excess fuel is discharged from the cylinder along with exhaust gases into the exhaust system. Because of this, the engine loses some of the power at each stroke, it literally starts to choke. In some cases, gasoline can simply fill the cylinders, and then it will not be able to burn at all.

Reasons for the formation of a rich mixture

Most often, a rich mixture is formed not due to the fact that more fuel is supplied than necessary, but due to the fact that less air is supplied than necessary. The most banal and common reason is clogged air filter... Alas, many motorists forget that some components need to be replaced regularly, even if they look like new. The air filter is one of such units, it needs to be changed at least every 30 thousand km, and even more often on powerful cars.

Also, a malfunctioning air pressure sensor can “cut off” the air supply. Together with it, the fuel pressure sensor works, which can also supply underestimated data to the electronic engine control unit. Based on them, the block begins to pump more fuel into the cylinders, enriching the mixture. She, as we learned above, impairs power and dynamics, the control unit does not like it, and it supplies even more gasoline. Hence - a greatly increasing fuel consumption.

The reason for the rich fuel mixture can be hidden in the very electronic unit engine control. These may be errors in his program, but also incorrect changes made to it. Self-taught craftsmen and simply unskilled craftsmen "tune" the control unit, deliberately increasing the proportion of fuel in the mixture. This way you can achieve a small increase in power, but it is much easier to upset the balance and achieve the opposite result.

The fuel pump can also violate the proportions of gasoline and air, pumping much more fuel into the system than is needed. And the most difficult reason to determine is the malfunction of the injectors in the cylinders. They can become clogged or deformed, and then the balance of the fuel-air mixture can fluctuate in any direction.

Consequences of driving a rich mixture

Nothing good riding on a rich mixture will not. If you do not solve the problem in time, then this can lead to the following consequences:

• burnout and other damage to the muffler and catalyst, because the ejected fuel starts to burn out in exhaust system - hence the black smoke, pops and shots;
• an oily residue forms on the walls of the engine exhaust system, which clogs it, and after a long time, a complete cleaning of the system may be necessary;
• the percentage of harmful impurities in exhaust gases increases sharply, which harms the environment and reduces the catalyst resource;
• unpredictable dips in dynamics can be very dangerous for you and for other road users.

So at the first signs of enrichment of the fuel mixture, it is better to immediately visit a car service. Moreover, the problem is very quickly and easily determined by the memory scanner on-board computer - it displays error P0172. Also, in many cases, repairs are inexpensive and fast enough.

December 18

Thanks to the gratuitous help of members of the forum-disputants, we finally opened. The pub was named Altbier, and many thanks to everyone for participating in this project. and from our side, we decided to give the forum users who visited our PUB a compliment from the institution. And also get your feedback, responses, criticism about our institution. It is very important for us)))
P.S. in order to get a compliment, you just need to say that you are from the dispute) Thanks everyone)

Modern cars are set in motion. It is characterized by a certain work pattern. A fuel-air mixture burns inside the chamber of this system. This means that by refueling the car with gasoline or diesel, the driver provides only one necessary element for the movement of the vehicle.

The fuel is mixed with air. gasoline or diesel. The fuel evaporates in front of the valves. In the cylinders, a mixture of fuel and air is burned by an electric spark. If it is issued, it means that the system has detected a deviation. It is a rich blend. But you can also independently see the malfunctions of the engine caused by such a problem. Every car owner should know how to fix it.

General concept

Delving into the concept of what is too rich mixture (WHA, Skoda, BMW, Chevrolet, etc.), a few words should be said about the fuel itself. It consists of gasoline (diesel) and air correlated in a certain proportion. Liquid fuel is supplied to the engine cylinders. This ratio largely depends on its quantity.

A rich mixture is a mixture in which there is more gasoline and less air than the norm. Since there is not enough oxygen inside the combustion chamber, the engine operation loses power. Because of this, gasoline burns out already in the muffler. Some auto mechanics call this state of fuel high in calories.

These violations are reflected in the external. They have a characteristic black carbon deposit, soot. There may be several reasons for this state of the engine system. They must be found and eliminated.

When the mixture gets rich

Mixing deviations appear as a result of certain malfunctions of the vehicle systems. The injector is responsible for the process of creating fuel. He prepares mixtures with a certain percentage of oxygen. It is this ability of the presented engine element that enables the engine to operate in different modes.

If necessary, the driver can, thanks to such a device, increase speed, cope with the rise, go to overtake, etc.

Determined by a mathematical formula. The ratio of 14.7 kg of oxygen per 1 kg of liquid fuel is considered normal. If, for some reason, the amount of oxygen in this formula increases, such a composition is called poor. If the amount of fuel in the mixture rises, the mixture becomes rich.

The car owner can independently adjust the level of oxygen supply to the fuel mixture. Errors made in this process lead to breakdowns and malfunction of the vehicle.

Signs of deviation

Rich mixture - VAZ, UAZ, BMW, Audi and other existing car brands - can be manifested by a wide range of deviations in the car's operation. If such violations occur, it is urgent to find out the cause of this engine condition.

In vehicles in which an auto scanner is installed, when the presented deviations occur, an indicator with the corresponding error code (P0172) lights up. The muffler may then emit loud bangs. This is due to the afterburning of air in exhaust pipe... This is one of the first signs of violations.

In this case, you can notice the appearance in the exhaust gases of black, gray shades. This is also due to an inappropriate way of burning out the fuel. The exhaust does not undergo any cleaning. The pipe contains a large number of atmospheric oxygen. Therefore, the exhaust gas takes on a characteristic dirty tint.

Driving a car

Too rich mixture manifests itself also when managing vehicle... Almost any driver will immediately notice this. The car becomes less dynamic. The engine power drops sharply. Since the combustion process in the motor chamber is slower, the mechanism is not able to operate at full strength.

In some cases, the car may not even run. But this is with very serious deviations in the ratio of fuel and air in the combustion chamber.

When driving a car, the owner may notice that the fuel consumption has increased. It is also a common symptom of engine malfunction due to rich mixture operation. This violation is simply explained. The engine does not operate efficiently under these conditions. The fuel mixture is not being used properly. To prevent low speed combustion, the engine begins to inject more liquid fuel into the chamber.

Main reasons

There are several main reasons for deviations in the air to gasoline ratio. The most basic of them can be deviations in the engine management system, as well as malfunctions of the air damper drive. An injector malfunction can also explain why it is detected rich mixture. Carburetor can also cause deviations if incorrectly configured. Clogging of the air filter is considered another factor in the formation of a rich mixture.

Often, improper actions of the car owner become the cause of violations in the fuel system. In order to reduce gasoline consumption or increase engine power, the driver may incorrectly adjust the system. As a result, he gets problems with the engine and the need for extraordinary maintenance or even repair.

Fuel supply deviations

Since the process of forming a combustible mixture consists of two main components (gasoline and air), violations are possible from the supply side of each of them. Excess fuel is detected much less frequently than lack of air. But the typical fuel supply disturbances should be considered in more detail.

Too rich mixture, the causes of which are related to the fuel system, can be caused by high pressure in the line. This deviation is caused by a malfunction of the fuel pump or regulation system. To check this version, a special fuel pressure gauge is used.

Deviations in the composition of the mixture can be caused by the adsorber. A large amount of gasoline is admitted through it due to a malfunction of the vapor recovery system.

May also be malfunctioning when closed, may be unable to hold fuel. This causes it to enter the chamber even with closed nozzles.

Air supply problems

Rich Blend Error, which is determined by the vehicle diagnostic system, is much more often caused by insufficient oxygen supply to the combustion chamber. There are several reasons for this violation.

First of all, the air filter can be elementarily dirty. For some reasons ( difficult conditions operation, driving on dirty roads) this element of the oxygen purification system may become unusable even earlier than the period specified by the manufacturer. Therefore, it is necessary to visually evaluate the cleaner. If it is dirty, covered with oil, it must be replaced urgently. Otherwise, the motor will quickly fail.

In some cases, the cause of an inadequate supply of air to the combustion chamber may be a breakdown of its flow sensor. This will help identify the reading system of the scanner. Sometimes a malfunction of the air pressure sensor in the manifold system is determined.

Automatic diagnostic system

If the vehicle diagnostic system shows that there is error "Too rich mixture", certain actions must be taken. To do this, you need to understand the principles of the scanner.

Air is supplied to the fuel when diagnosing the MAP sensor and the lambda probe. Perhaps it is caused by deviations of these particular systems. However, in addition to them, problems may be associated with deviations in thermal gaps (engine with LPG), with mechanical damage to sealing materials, insufficient compression or deviation during the operation of the timing.

To understand why automatic diagnostics indicates such an error, the car owner can take several actions. First of all, it is required to analyze the information provided by the scanner. Further, you can artificially simulate the conditions for the occurrence of such a malfunction.

The next step may be to check the components and mechanisms, for example, contacts, the absence of suction, as well as the operability of systems associated with the supply of fuel and oxygen to the combustion chamber.

Eliminating system error

If the diagnostic system indicates that the vehicle is using a rich mixture, a number of actions must be taken. The faulty unit is found in a sequential check of each system. For this, the JOT, MAF sensors, as well as the lambda probe are checked with a multimeter.

If no deviations are found in these systems, you need to pay attention to the candles, coils and wires. Next, the fuel pressure is measured using a pressure gauge, and the ignition marks are also checked.

Then check the seals and connections at the air inlet as well as the exhaust manifold. There should be no suction. After carrying out all the manipulations and eliminating the malfunction, the fuel supply adjustments are reset. In this case, long-term programs with respect to this setting return to their original value.

If in fuel tank preparing too rich mixture, the first thing experienced auto mechanics recommend to do is to reset additional settings injector operation. If the owner produced independent settings fuel control system, he could make serious mistakes. A rich fuel mixture will lead to inevitable engine damage very soon.

If the cause of the deviations is related to the nozzle system, this can be determined visually. With such a malfunction, traces of fuel combustion appear on the outside of the injector.

Smoke and soot can also be found on one side of the copper O-ring. Such deviations are caused by incorrect installation of the injector. If the O-ring is not in place, similar malfunctions are also possible.

Rare breakdowns

Experts say that 90% of all errors “are related to injector adjustment. It is not difficult to eliminate it. The main thing is to pay attention to the wrong work car engine.

The most rare, exotic faults are considered to be the engine control unit, as well as the poor condition of the contacts. Sometimes there are cases of poisoning of the oxygen sensor. An experienced specialist is able to identify such deviations. In this case, not every car owner can solve the problem on his own.

By looking at what a rich mixture is, you can understand the dangers of such a situation. If unforeseen situations arise, it is better to contact the service center. The service points have necessary tool, with which you can make diagnostics. This will save the car's engine.

Everyone knows that a car engine does not run on pure gasoline, but on a mixture of gasoline and air, the so-called fuel-air mixture. It is calculated that for the complete combustion of one kilogram of gasoline, fifteen kilograms of air are needed, that is, the optimal composition of the fuel mixture is approximately 15/1 - one kilogram of gasoline for 15 air. In this case, the power and economic indicators of the engine will be normal (balanced).

Reducing the proportion of air causes the fuel mixture to richer. Allowable, within the proportion - 13/1. Such a mixture is called rich and is necessary for the engine to operate at full load in order to fully unleash its power potential.

Reducing the proportion of air to less than 13 kg per 1 kg of gasoline leads to the formation of a rich fuel mixture. A rich fuel mixture, in contrast to a rich one, leads to a decrease in engine power and throttle response, since gasoline does not completely burn out due to a lack of oxygen.

With a ratio of 5/1, the fuel mixture is considered over-enriched, and the engine generally refuses to work on it, gasoline simply does not ignite.

For the correct mixture formation specifically for each operating mode of the engine, either the carburetor or the engine control system (ECM) is responsible.

We will be interested in a rich fuel mixture, since the engine runs on it, but its work in this case leaves much to be desired and something urgently needs to be done about it.

Consider the signs and reasons for the formation of a rich fuel mixture on carburetor engines VAZ cars.

Signs of a rich fuel mixture

- Black carbon deposits on spark plug electrodes

- Black smoke from the muffler

— Cold engine easier to start up than hot

— High consumption fuel

- Decrease in engine power and throttle response

The main reasons for the formation of a rich mixture

Carburetor malfunction or fuel system:

- GDS air jets are clogged;

- fuel and (or) air jets GDS according to their calibration data do not correspond to the standard for this engine;

- high fuel level in the carburetor float chamber;

- the economizer of power modes is faulty;

- the EPHH system is faulty;

- pumps over the fuel pump.

Other malfunctions with similar symptoms

Ignition system malfunctions

- too early ignition timing;

- one or more spark plugs are faulty;

- defective armored wires, slider, distributor cover;

- faulty centrifugal ignition timing regulator;

- the ignition coil is faulty;

- too small a gap between the breaker contacts (for contact system ignition).

Engine malfunction

- the valve timing is knocked down (the timing belt jumped);

- the elements of the cylinder-piston group are worn out;

- too large clearances in the valve drive.

Notes and additions

A rich mixture is a violation of the "golden" rule. Within certain limits, a small enrichment can give an increase in power, but everything has a limit beyond which a malfunction occurs.

How to get the mixture back to normal

If the problem is similar to those described above, you should contact a competent diagnostician. Sometimes you can eliminate the cause of the rich mixture by adjusting throttle or an injector. In other cases, replacement of "flying" sensors is required. Therefore, you need a specialist who has the knowledge, experience and equipment to carry out a comprehensive diagnosis.

Chip tuning can save you from problems with the oxygen sensor (lambda) - this is one of its functions. When choosing this solution, the reprogramming of the control unit (ECU) should be trusted by professionals.

Often from the diagnostician you can hear "you have a rich mixture." For an unprepared car enthusiast, it sounds mysterious and disturbing. Let's see what a "rich mixture for injection engine"And how bad it is

What should be the fuel-air mixture

Under ideal engine operating conditions, the amount of air should be 14.7 times the amount of fuel. That is, there are 14.7 “drops” of air per drop of fuel. This ratio is called stoichiometric and the most useful in terms of engine efficiency.

A rich mixture is a violation of the "golden" rule. Within certain limits, a small enrichment can give an increase in power, but everything has a limit beyond which a malfunction occurs.

How to tell if a mixture is rich

Several characteristic features:

Reasons for a rich mixture on the injector

• Injectors or O-rings defective;
• Air filter heavily clogged;
• Excessive pressure in the fuel line;
• Faulty or dirty mass flow or air pressure sensor (DFID-MAF-MAP sensor);
• Incorrect operation of the adsorber valve;
• Malfunction of the oxygen amount sensor in the exhaust gas (lambda probe, oxygen sensor). When it fails, the lambda probe "sticks" in one of the positions and gives incorrect readings instead of actual information. The control unit is forced to rebuild the fuel supply, bringing the mixture ratio out of the norm.