Why is there black smoke coming from the muffler? Soot from the exhaust pipe: what is the reason? Causes of soot from muffler

While the engine is running, the color of the exhaust gases may be different; this is a kind of indicator of the condition of your unit. On corrected engines, upon startup, white smoke comes out for a short period of time. If the engine is faulty or in poor condition, it may produce white, black, blue or gray exhaust.

If there is constant white, black, blue or bluish smoke when the engine is running, this is a reason to check it.

Let's look at why black smoke appears when starting the engine, what blue smoke indicates, and also why it comes out of the engine goes white smoke.

What does car exhaust say?

The exhaust may be of different colors, sometimes if you notice smoke that is not typical for your car, you should think about it and check the condition power unit.

White exhaust may appear after long-term parking car. This is due to condensation that accumulates in the exhaust system and begins to evaporate when the engine starts. Outside temperature air also affects the formation of white smoke. The colder it is, the more and longer the smoke comes out.

Therefore, in frosty weather, smoke can constantly come out. It's worse if white smoke comes out in warm weather. This may indicate that the cylinder has gotten into working fluid from the cooling system.

In this case, it is necessary to disassemble the engine, remove the cylinder head, change the cylinder head gasket, repair cracks, check the tightness of the head, and the like.

To check and confirm that liquid has entered the cylinders, you need to perform a number of actions:

• Start the engine, open the cap of the cooling system expansion tank and check for fluid bubbling. If bubbling is present, it means that gases are breaking into the cooling system. When the engine is turned off, the coolant level decreases, as part of it goes into the engine cylinders.
• You should pay attention to the color and condition of the liquid in the cooling system, the smell of burning, the presence of greasy stains on the surface, changes in color, density, etc. This may indicate microcracks and defects in the motor.
• It is necessary to check the oil level; there are often cases when it rises as a result of liquid from the cooling system entering it. As a consequence, motor oil liquefies and becomes cloudy, an emulsion appears in it.

It is better not to use the engine until the problem is resolved, so as not to aggravate the situation. In the worst case, as a result of a large accumulation of fluid in the space above the piston, a hydraulic shock can occur, which will damage the power unit and lead to expensive repairs.

Black exhaust from muffler gasoline engine issues, as a rule, at startup, this occurs due to problems in the power system. In this case, the working mixture of fuel and air is greatly enriched, and more fuel enters the combustion chamber than necessary. The signs of this situation are as follows:

• Starting the engine is difficult;
• The spark plugs are filled with fuel;
• When starting, the power unit malfunctions and is not stable;
• Loud noise in the muffler operation, popping;
• High fuel consumption;
• The engine does not produce its former power;
• The on-board computer displays an error;
• Smell of gasoline when the unit is running

When the engine is running, the color may vary from gray to jet black. This is due to the fact that during operation a large amount of soot accumulates and over time it is released into the atmosphere.

There are many reasons that lead to fuel supply failure. You need to start looking for problems with the fuel supply systems. On carburetor engines, it is necessary to check the metering device, fuel and air jets, and the float chamber.

It is necessary to check the ignition system; it happens that if some element fails, such as the ignition coil, high voltage wires, spark plugs, a malfunction occurs in the engine as a whole.

It is necessary to check the condition of the air filter; if it is dirty, the mixture entering the cylinder will contain a lot of fuel.

In engines with injector, the electronic engine management system sometimes fails. By transmitting incorrect data to the control unit, the controller increases the fuel supply. Which in turn leads to an excess of the fuel mixture.

Also, the injectors in the engine can lose their seal and spill fuel into the combustion chamber.

Filling spark plugs with fuel not only causes an excess of fuel, but also many other problems. For example, washing off the oil film from the cylinder walls, resulting in severe wear of the cylinders and piston group. In addition, a large amount of fuel enters the engine crankcase, which leads to oil dilution.

In any case, the motor needs full check, configuration and troubleshooting, otherwise the consequences will be very expensive.

Blue smoke when the engine is running indicates that engine oil is entering the combustion chamber.

Increased engine oil consumption will indicate that oil has entered the cylinder. Reasons for oil penetration:

• Severe wear of piston group parts;
• Damage to the gas distribution mechanism

When parts wear out, they fail piston rings, defects appear on the piston and cylinder walls.

If the gas distribution mechanism breaks down, there is no seal in the area of ​​the valve stem and valve guide.

For repairs, it will be necessary to replace the valve seals. Measure the compression in the engine. If the reduction in compression is insignificant, then as work progresses, the blue smoke disappears, since the gaps decrease when warmed up. If the gaps are large and the smoke does not stop, repairs must be made.

Let's sum it up

So, to eliminate black, white, and blue smoke, sometimes it is enough to replace the filter and clean the injectors. Whereas in more serious cases it is necessary to repair the engine and its mechanisms.

It must be remembered that if the engine suddenly starts smoking black, you need to replace the fuel, since low-quality fuel, with a high content of additives and undesirable impurities, leads to a change in the color of the exhaust and difficulties in combustion of the mixture.

Do not forget that the timing belt must be installed according to the marks, the valves and valve timing must be clearly adjusted, the thermal clearance of the valves must be correctly installed. Spark plugs, during diagnostics, will help assess the condition of the engine.

The stability, reliability and durability of the power unit directly depends on everything, and many other indicators.

As I promised in the last article, I will analyze all types of smoke. Today is the turn of “black smoke”; it can appear on both diesel and diesel engines. Why this happens and what it means is detailed in this article...

You know, to great relief, this does not indicate a serious breakdown of the engine or its auxiliary systems. But if this problem is not eliminated in time, then it is possible to bring the supply system, the fuel ignition system, as well as the engine itself to a deplorable state, because they are the causes of black smoke from the muffler.

Appears: - in the form of a thick black exhaust from the muffler, it comes out especially strongly when you press the gas pedal. Moreover, the car does not operate stably, the engine often “troubles” and starts poorly in the morning (especially in winter). Fuel consumption increases.

Main reasons

Black smoke indicates that the fuel-air mixture is too rich (over-rich). A lot of fuel enters the cylinders, which does not have time to burn effectively, so the exhaust is repainted black. It is much more toxic and harmful than normal exhaust, because it cannot even promote the combustion of excess fuel in the exhaust.

The main reason for this is a malfunction of the fuel supply system, which occurs in all types of engines. internal combustion ().

The second reason may be a malfunction in the ignition system; the fuel is not ignited in the chamber and therefore the raw mixture goes directly into the muffler, and the engine will.

With carburetor ignition

With the carburetor, everything is quite simple - if the exhaust is painted gray and black, there is instability in operation; first of all, you need to look. Most likely, there is an overflow in the float chamber.

This happens for two reasons:

1) The “needle” (needle valve) is faulty; it can stick or, on the contrary, leak excess fuel.

2) The jets are clogged and coked (from our fuel). Small "nozzles" with precise size.

You need to disassemble the carburetor and clean it; if that doesn’t help, then you need to buy a repair kit and replace the “needle” and jets and correctly set the gasoline level in the chamber.

Injection option

Here everything is a little more complicated on the one hand, and simpler on the other. The injector does not have chambers with needle float, etc., it is a completely different system that supplies the fuel-air mixture using electronics. Injection into the cylinders occurs using special devices - “injectors”, hence the name.

The main causes of black exhaust:

1) Often the cause is the injector itself; it simply becomes clogged and cannot supply fuel normally. There is an accumulation of pressure, and then a “strong” injection, often with excess. Engine operation will not be stable, then low revs, then high – in simple words will "float". In such a situation, you need to clean the injectors, there are many different ways, from removing the fuel rail, to special agents that are added to gasoline - it’s up to you, but after such manipulation you can often get rid of black smoke from exhaust pipe. Performance is restored. Cleaning should be done at least once every 60 - 70,000 kilometers.

2) Since the system is automated, it monitors various cycles using sensors. So, if the sensor is faulty, it will either prevent the car from starting at all, or it will supply too much fuel. Here you are unlikely to be able to diagnose the breakdown yourself; you need to go to a service station.

3) Fuel pump. Typically, injectors have it in the tank; there have been cases when it supplies increased pressure. Which also led to overflow in the injection chambers. Again it needs to be replaced.

Diesel engine

In general, the diesel engine is the record holder for black exhaust. The thing is that it has a slightly different fuel ignition system (from pressure), and it runs on diesel (diesel), and even in normal condition it produces a slightly blackish-blue exhaust. Just remember our KAMAZ trucks. However, recently they have been fighting against such exhaust, because it is very toxic and poisonous, it contains a lot of lead. Therefore, now almost all diesel engines are equipped with “”, to please EURO 5 standards; it cleans the exhaust and prevents harmful substances from entering the air.

Causes of black smoke:

1) This is a simple failure particulate filter, it just needs to be replaced. However, the smoke intensity will not be as high.

2) The high pressure pump is broken. There is excessive overflow. It just needs to be changed.

3) Incorrect ignition timing. Needs to be adjusted.

What can such smoke from the exhaust pipe cause?

If you don’t take action in time, you can run into serious problems. So for example injection cars, the catalyst dies quickly, but replacing it is very expensive (many even just remove it).

Also, if there is a large overflow through the “injector”, this can almost lead to a problem, because sometimes fuel is supplied in liquid form, and not in an air mixture. This is a very dangerous, complex breakdown.

On a diesel engine, from a large volume of fuel, the block can rupture, because the pressure there is even greater than that of gasoline engines.

As you can see, black smoke itself does not cause complex malfunctions, but if you do not react to it in time, it can result in big problems.

Significantly different from gasoline ones. But the problems with them are almost the same as with gasoline units. After reading car forums, you can see many different topics where certain problems are discussed. But you can especially often see topics where car enthusiasts complain that diesel engines periodically emit black smoke from the exhaust. Let's figure out what the problem is and why this phenomenon occurs. Let's also see how this problem can be solved.

Making a diagnosis based on exhaust colors

Diesel engines, as well as gasoline engines, can have exhausts of different colors. More often it is white, bluish, gray and black smoke.

Let's start with white. Often white is the name given to smoke with a bluish tint. This happens when the turbine is destroyed and the lubricant gets directly into the intake tract. In such a situation, bluish smoke pours out of the chimney. But an inexperienced car enthusiast will easily mistake it for white smoke. And if you smell it, then it’s immediately clear and understandable what the reason for its appearance is.

Many people have burned vegetable or butter in a frying pan. The smell is about the same. This smoke can also be confused with steam, which is more often observed in the winter months from the exhaust of not only diesel cars. It's all because of the water that appears as a result of combustion.

Later, after the engine has warmed up, the steam will not be noticeable, although this can be easily checked. You just need to place your palms near the exhaust. The palm will be slightly damp. This steam causes significant inconvenience when tuning the engine, especially in winter. For high-quality settings, you have to warm up the unit for a long time. And in cold weather the adjustment may not be possible at all.

White smoke is a sign of a serious problem

If the smoke from your diesel engine is not steam, then it is definitely coolant that enters the combustion chambers. Typically, a cylinder that has been filled with cooling mixtures does not have the ability to idle. Therefore, the motor can trip.

How does coolant get into the cylinders?

Coolant enters the cylinders due to the unsatisfactory condition of the intake manifold gaskets. Also, the cause may be a burnt-out cylinder head gasket, and for diesel engines, most often it may be a cracked cylinder head. In a cylinder head crack, the reservoir, often full of liquid, also completely disappears into the pipe.

Repair

If you find a crack in the cylinder head, then we can only recommend replacing the head. However, prices... Therefore, many car enthusiasts do not disdain contract details. These are used parts from Europe.

Cracked cylinder heads can be repaired, but we will not recommend this technology because during such repairs a hole is drilled that will fit into the crack, and then a copper rod is pressed into the hole. There will be no blow-by, but one of the cooling valves will be blocked halfway. Such a head will have a significantly reduced resource.

Blue smokes

Those who had smoke coming out of diesel were worried at the sight of blue smoke.

Blue, and on some engines it can be gray, on a working engine it is often caused by late injection. This problem has been mentioned more than once; many car enthusiasts have managed to discuss this topic up and down.

Experts say that blue smoke is not scary. In most cases, the problem of late injection is associated with the natural process of wear of the fuel injection pump, naturally, if no one touched the pump.

Causes of Blue Smoke

The fuel pump in our conditions works as follows. The set of parts in this assembly constantly rotates, works, and rubs. And lubrication is provided by the pumped diesel engine. As long as the diesel engine is moderately oily, the pump can operate in this mode for a very long time. But when the cold comes, fuel tanks diesel engines are filled with winter diesel fuel. Everything about it is excellent, but there are no lubricating fractions at all. Well, or almost absent. All its fat content, along with various paraffins, was removed at the oil refinery.

So, when winter comes, most diesel injection pumps operate without lubrication and are subject to severe wear. Because of this completely natural, but already too rapid and increased wear, the injection advance is reduced. Diesel fuel stops heating, and the cylinder stops working normally. The engine jerks and shakes. Fuel that does not have time to burn ends up turning into blue smoke. Some engines produce black smoke from the exhaust. If the engine is warmed up, then it will stop smoking, or at least the amount of exhaust will decrease. In this case, the fuel has time to warm up and ignite.

If the power unit has low compression characteristics, then the temperature in the combustion chambers is lower than necessary. And the fuel will not ignite. If the unit is equipped with a pair of cylinders with good compression, the cylinder with less compression will not work.

This picture often happens in parking lots. The cars are trying to start, and the entire area is filled with blue smoke. But sometimes diesel produces black smoke from the exhaust pipe. After warming up, the smoke will disappear. After all, the temperature in the engine is rising, and the temperature increase even in worn-out cylinders will be enough for ignition.

An incident from life

Mechanics tell one story on this topic. The cylinder head gasket on the unit was replaced. After the engine was assembled, we discovered strong shaking at idle. After a couple of kilometers these vibrations stopped, and after a couple of minutes of idling the shaking reappeared.

Mechanics analyzed this situation and found out that the new gasket is a little thicker. Until the diesel engine warmed up to operating temperature, it didn’t work exactly.

So, the main cause of blue smoke is late fuel injection and low compression performance. Many modern engines have a device that injects a little earlier. Cars work harder, but the fuel in the cylinders heats up and burns without smoke, that is, at all. Then the unit heats up, the coolant heats up the actuators, and they return the injection advance piston to its rightful place. The motor runs smoother and more pleasant.

How to remove blue smoke

If the engine shakes and the diesel produces black smoke from the exhaust pipe, well, or blue, then you can safely turn up the fuel injection pump. But first you need to see if there is enough fuel. If the pump does not have enough fuel, then the pressure decreases, and this allows the spring to move the timer to a later injection. This will cause shaking.

Black smoke

Such smoke can be observed if the fuel does not burn completely. This happens if too much fuel is supplied or the wrong fuel mixture is supplied. If too little air is supplied to the engine, the effect will be the same as if too much fuel was supplied.

Why does black smoke come out of a diesel exhaust pipe?

A larger volume of supplied fuel is usually a signal of either incorrect adjustment of the fuel injection pump, wear of the injectors, or wear of the speed controller in the pump.

Any fuel pump is equipped with a special adjusting screw. It is used to adjust the volume of supplied fuel. With this screw you can only roughly adjust the volume. If this screw is tightened, then the volumes increase. And where there is an increase in volumes, there is also an increase in idle speed. But the speed can be significantly reduced. Then you can increase the power. But black smoke from the exhaust pipe will continue to drive diesel. If the adjusting screw on the fuel injection pump is screwed in even more than it should be, the unit will practically stop reducing speed.

Nozzle wear

Here we can assume that the needle does not fit tightly enough into its seat. And the level of pressure that should raise this needle decreases. This leads to excess fuel entering the combustion chambers. It is superfluous, if only because it is supplied not in a spray form, but in drops. It takes a long time for these droplets to heat up and ignite. Hence the black smoke from the exhaust pipe and increased (diesel) fuel consumption.

The saddest thing

One of the saddest breakdowns that beset diesel owners is inevitable wear and tear. fuel pump. As already mentioned, the guts inside the pump operate without lubrication. While diesel still lubricates something in summer, in winter it doesn’t. And domestic fuel is generally of low quality. This is where the insides of the pump wear out.

When the gas pedal is pressed very sharply, for example, in order to quickly move off, the injection pump lever is switched to increase the volume of fuel supply. This lever will rest on the support. And the position of this very support has already been adjusted by the regulator. Therefore, it will not be possible to increase the volume too sharply. So, by pressing the pedal, the driver only wants to give a larger volume of fuel. And it’s not at all a fact that this will lead to an increase in turnover. This directly depends on how worn the speed controller is. If it is in normal condition, then the car will start with gray smoke. If the wear is large, then the diesel will spit out black smoke from the exhaust pipe in a large cloud.

About lack of air

Also, dark gases from the pipe can sometimes be caused by a lack of air. But in this case, the exhaust will not be black, but rather gray or dark gray. At the same time, a decrease in power is observed.

This can lead to clogged filter air supply. This is by no means a rare case, and it happens to everyone from time to time. It has been proven not 10 or 100 times by bitter experience that only 15 minutes in a traffic jam in front of a KamAZ truck with black smoke coming out of the exhaust pipe is enough. The diesel is burning, and the new filter of the one standing behind can now be thrown into a landfill. But this happens if KamAZ is incorrectly adjusted, although no one has it adjusted.

Also, a lack of air can be observed due to incorrect operation of the EGR and throttle valve, incorrect clearances in the timing valves. Also among the reasons may be incorrectly set gas distribution marks, turbine malfunctions.

When the car is equipped with a turbine and you see black smoke from the exhaust pipe of a diesel turbo, then it is worth checking the boost. Most likely, that's the problem. It is also worth looking for cracks in the fuel or air system pipes.

One of the car owners poured cleaning fluid into the car fuel system. After traveling a bit, high speed When driving uphill, the car puffed out black smoke. But after puffing a little, the smoke disappeared and has not appeared since then. At the same time, he checked all the above reasons. He believes the additive helped. Bigger car didn't smoke. So, perhaps the cause of the smoke in this case may simply be soot from the fuel system, especially if the diesel engine is equipped with a converter. Sometimes the filter needs to be cleaned from time to time.

Another reason for black smoke from a diesel exhaust pipe

One of the owners diesel car the engine suddenly began to smoke. During the autopsy, nothing intelligible could be found. But after reading all kinds of forums and talking with other diesel owners, it turned out that the problem was in the ignition.

After opening it again, a control valve was found on the ignition unit. He was advised to hit the adjusting bolt. After that the car stopped smoking. It turned out that it was the ignition angle.

When the ignition is turned on, the working sensor crackles. What to do if black smoke appears from the exhaust pipe (diesel)? No matter what ignition it appears, the sensor should be removed. If the engine has stopped smoking and the car is running smoothly, then it’s time to change this element.

Black smoke and cold start

A study of the forums showed that many people complain about smoke when diesel engine. Some people say that this is a fuel injection pump, but more experienced car enthusiasts say that this is not so.

It is believed that this phenomenon is quite normal. Usually it is short-lived. This can be explained by the fact that during a cold start, an over-rich mixture is supplied to the cylinders. Hence the black smoke from the exhaust pipe. Diesel often does this when cold. Therefore, there is no need to panic about this.

The situation with the Kia Sorento

Let's give a specific example. One of the owners of this car produces thick, black smoke when pressing the accelerator pedal. When moving, the car is very reluctant to gain momentum.

A scan was carried out for possible errors in electronic system, however there are no errors. Analysis of the operating parameters also did not give the desired result. At first glance, there is simply no defect. The balance of the injectors is in normal condition, no serious deviations have been noticed, the turbine produces a normal level of pressure, but there is black smoke from the diesel exhaust pipe" Kia Sorento" still gave out. When measuring the readings, they thought about the USR. This is a valve that regulates exhaust gases.

Having examined it, they found serious soot deposits behind throttle valve. After removing the exhaust gas pipe, soot and oil were also found in the intake tract. In the end everything was removed and cleaned. But a more detailed examination of the valve itself revealed damage to its seat. As a result, the valve was replaced.

As a result, there is no smoke, and the car drives noticeably better.

Coommon Rail System

Similar problems are also noticeable here. Many people complain about black smoke from the exhaust pipe - the Comon Rail diesel engine successfully provides this result during a cold start. Car enthusiasts say that this may be due to low-quality fuel or problem injectors. So, the fuel is not sprayed, but poured. That's why there's black soot. And when the engine warms up, the injectors pump fuel in normal mode.

As a conclusion

We have found out the common and popular causes of smoke. Also, when starting “cold”, a little black smoke is normal for a diesel engine. Most problems can be easily fixed on your own. However, the problem is that black smoke matches all the symptoms, and it is not clear what to treat. Therefore, if you have black smoke coming from the exhaust pipe, the diesel engine is shaking and jerking, it is better not to tempt fate. In this case, you should give the car to experienced specialists for diagnostics.

So, we found out why black smoke is coming out of the exhaust pipe. Diesel is a complex thing, so such cars require constant care.

When the engines were only carburetor, black exhaust from the muffler meant, in the vast majority of cases, only one thing - worn valve seals. Through which oil leaked and burned along with gasoline in the combustion chamber. However, even then, serious specialists, like this, “by eye,” determined the difference between such a malfunction (now called blue exhaust) and a situation in which the exhaust was truly black.

Causes of black exhaust

When gasoline does not burn, but cokes

In fact, the exhaust is colored black by particles of unburned, charred fuel, which simply did not have enough oxygen to detonate, and which turned into coal flakes due to the effects of temperature. They give the exhaust from the muffler a black color. Moreover, this process is usually accompanied by a malfunction of the engine, “triple” on idling, a drop in traction (very noticeable, by the way). Well, this malfunction should be eliminated by adjusting the flow of oxygen into the combustion chamber.

When air flow is not enough

It's actually very simple. The process of fuel combustion in an engine begins with gasoline flowing from the tank into the carburetor (or into the nozzle, if we are talking about a diesel engine), or into the injector. Here it is sprayed, mixed with the incoming air, turning into a flammable mixture, which detonates in the combustion chamber, alternately pushing the pistons. And if the air flow is not enough, then black exhaust from the engine is the only possible option. An over-enriched mixture is simply formed, which does not have time to burn completely. After all, even in the event of a strong fire, remember, first of all they try to block the access of air and oxygen to the source of the fire. And then there will be nothing left to burn...

In this case, you need to adjust the fuel level, clean the carburetor, jets, maybe even everything will cost you just by replacing the air filter, which, when clogged, does not allow enough air to pass through to create a mixture with the correct ratio of atomized fuel and oxygen.

Abrasive processes in the combustion chamber: what threatens black exhaust

Black exhaust always indicates increased fuel consumption when the engine is running, but this is a consumption that does not affect the increase in power. On the contrary, there is a drop in power, and a significant one. And now - the most important thing.

• The fact that black smoke is pouring out of the muffler is not the worst thing.
• The fact that this black exhaust is accompanied by a drop in power (at which the car in fourth gear develops at most 100 - 120 kilometers per hour) is also not the worst thing.
• Even the fact that gasoline consumption doubles is not the worst consequence.

Black exhaust from the muffler threatens serious engine problems due to the fact that coal particles - they fly out not only from the muffler.

They enter the combustion chamber and, without burning, remaining there, in the space in which the pistons “walk”, stick to the walls of the piston liners, acting as a kind of abrasive, undermining the walls, which in theory should be perfectly smooth and polished . This is what the notorious black exhaust is. It is capable of reducing the service life of the engine by an order of magnitude, several times, causing a complete repair (with grinding or replacement of liners).

And unburned excess fuel can enter the lubrication system, diluting the oil, making it unsuitable for lubrication. Sometimes this process is so intense that the oil level in the crankcase increases noticeably. Which, of course, also does not contribute to the long-term operation of the engine. As well as the fact that gasoline that gets on the walls of the pistons and cylinders simply washes away the lubricant. As a result of all this, small scratches, and maybe even serious scuffs, may form on the walls, which are not at all conducive to the normal operation of the engine.

How to get rid of black exhaust

Carburetor malfunctions...

How to deal with it? How to eliminate a malfunction in the fuel supply system and establish the process of creating an enriched combustible mixture in which air and atomized fuel would be contained in the proportions necessary for normal engine operation? In fact, you need to look for the true cause of the malfunction. As already mentioned, this may be (if we are talking about carburetor engine) clogged air filter, which does not allow sufficient air into the system. Black exhaust from the muffler may be a consequence of a clogged hole in the nozzle through which air does not flow, or the reason may lie in the excessive supply of gasoline (if the float chamber is incorrectly adjusted and the fuel level in the carburetor goes off scale).

...injection and diesel...

If we are dealing with injection injection, black exhaust from the muffler may also indicate a malfunction of the fuel flow sensors (these units themselves are designed to regulate the amount of incoming air in accordance with a given norm). Or that the injectors are leaking, which, by the way, can be very relevant in the case when black exhaust from the muffler is observed when the diesel engine is running.

Although with diesel, of course, there are certain nuances. During a cold start, black exhaust will be observed in any case. Moreover, a cold start for a diesel engine is a serious test. It is not for nothing that in modern cars equipped diesel engine, a preheating system is always provided. But even this does not save you from exhaust emissions in the initial stages of operation of an engine running in a cold state.

Difficulty of repair: sometimes you can do it yourself, but sometimes you have to turn to specialists

Here it is important to simply orient yourself correctly and understand whether the exhaust has cleared quickly enough, whether the engine is shaking at idle, or whether there is a drop in power and increased consumption. If there is at least one of the listed malfunctions, get ready for trouble. Either not very large (adjustment), or quite serious. Up to replacing the piston group rings, or the entire group itself.

To eliminate a malfunction such as black exhaust from the muffler, it may also be necessary to intervene in the operation of the fuel pump or turbocharger (up to and including replacement), because the exhaust may also mean a failure in the fuel supply system. When gasoline is supplied too abundantly, the system for creating a combustible mixture simply cannot cope with such an amount. You may also need to adjust the pressure in the injector nozzles. These are problems that you probably can’t handle on your own. You'll have to contact a specialist.

To preserve engine life...

Be that as it may, you should clearly know that black exhaust is dangerous not because it spoils the environment (soot flies out of the muffler and stinks of gasoline), but also violates normal work engine, leads to increased consumption fuel and reduces the efficiency of its operation. You should always remember that particles of coked fuel not only fly out of the muffler, but also get into piston group, becoming an abrasive and rapidly wearing out the polished (ideally, like a mirror) working surface of liners, pistons and sealing rings.

This can lead to a noticeable drop in the engine’s operating life, and instead of the required, say, according to the passport data, 500 thousand kilometers ( modern cars designed for approximately the same service life) before repair, the engine will work an order of magnitude less. This is why black exhaust from an engine muffler is dangerous in the first place.

Smoke from the vehicle exhaust serves as a diagnostic sign and indicates a malfunction in the engine. Let's talk about what the black and white color of a car exhaust affects.

Causes of white smoke

At temperatures below 10 o C, white steam is formed even on a well-heated engine, and at frost temperatures of -20-25 o C it acquires a thick white color. So, the colder it is environment, the denser the smoke from the exhaust pipe is. In addition, the color and saturation of the steam is affected by air humidity: the higher it is, the thicker the steam.

The appearance of white smoke on a warm engine due to coolant getting into the cylinders. The water contained in the coolant does not have time to completely evaporate during fuel combustion and forms a rather thick white smoke. Its shade depends on the composition of the coolant, weather, and lighting outside. Sometimes it looks gray, reminiscent of an “oily” exhaust. It is easy to distinguish water vapor: it immediately dissipates, and after oil smoke a bluish fog remains in the air for a long time.

It is not difficult to clarify that it is actually water and not oil that is emitted from the exhaust. To do this, on a well-warmed engine, briefly cover the muffler hole with a sheet of paper. Drops of water from the sheet will gradually evaporate and will not leave obvious greasy marks.

All problems associated with white smoke from the exhaust pipe require not only eliminating the direct causes. Since defects are usually caused by engine overheating, you should check and eliminate malfunctions in the cooling system - it is possible that the thermostat, the fan switch sensor, the fan itself are not working, the radiator, its plug, hoses or connections are leaking.

If white smoke and accompanying defects are noticed, then the vehicle cannot be operated. Firstly, the defects progress quickly. And secondly, running the engine on a water-oil emulsion sharply accelerates the wear of parts, and after several hundred kilometers without overhaul Sometimes it’s no longer possible.

Causes of black smoke

Reasons:

• Air filter clogged (