The petrol engine smokes black smoke. How oil gets into the cylinders

20.04.2019

On our roads you can meet cars in which literally pours out of the exhaust pipe
smoke. In some cases, this is a symptom of a serious engine problem. Moreover, they are subject to this petrol units as well as diesel. Experienced motorists already by the color and nature of the exhaust, they are able to diagnose the car. However, in some cases
smoke of the same color has different causes. Why did the engine start to smoke heavily?
What could be the reasons? Let's try to figure it out.

Exhaust color troubleshooting

First of all, it is necessary to fix all the accompanying circumstances, whether it is a deterioration in dynamics, increased fuel consumption, a large waste of oil, and others. Together with the color of the smoke, they can give a more or less clear picture of the malfunction.
Color exhaust gases a "sick" engine has:

White;
Blue;
Black.

White smoke

In this case, it is important to distinguish the smoke itself from the usual white vapor that does not promise any trouble. Such steam appears in perfectly serviceable cars at low ambient temperatures. The fact is that water vapor is always inevitably present in the exhaust. They enter the cold exhaust system, condense and become visible, and even droplets of water appear on the exhaust pipe. As it warms up, the degree of condensation decreases and the steam becomes less. In more cold weather the white vapor goes stronger. In no case should you be afraid of this.
In a situation where the weather outside is not very cold, and the engine is warmed up to operating temperature, but the exhaust comes out of the pipe with white steam, most often the coolant that has entered the cylinders is to blame. This happens when the head gasket is leaking. This fluid contributes to the formation of exhaust with a thick white vapor and a pungent odor. In order to make sure that the diagnosis is correct, you can resort to a simple old-fashioned method. It is necessary for some time to close the hole in the exhaust pipe with a sheet of plain paper. Drops form on it. Then, you should wait until they dry. Water droplets without oil will evaporate and leave no greasy marks. In addition to a leaky gasket, a crack in the block head can also be to blame for the ingress of coolant into the cylinders. There are times when fluid enters the cylinder through the intake system, in particular, through a leaky intake manifold gasket. It must be understood that such troubles can have both Gas engine as well as diesel.
All malfunctions that are associated with white exhaust require immediate elimination. Moreover, it is necessary to eliminate not only direct causes, but also possible faults in the cooling system. Quite often, direct causes are generated by engine overheating. In this case, it is necessary to check the operation of the thermostat, the fan and the sensor for turning it on, the tightness of the radiator, the plug expansion tank and cooling system hoses.

blue smoke

Why did the engine start to smoke a lot of blue exhaust? This question often worries owners of new cars. If bluish smoke is coming out of the exhaust pipe, this indicates that the engine has entered the cylinders. engine oil. The color itself can have shades from slightly blue to deep blue, and sometimes white-blue. This smoke, unlike steam, slowly disappears into the air. If you carry out the old-fashioned test mentioned above with paper, then greasy drops will definitely remain on it. A motor that smokes heavily with such smoke inevitably consumes a lot of oil. Often oil consumption increases so much that it takes more than a liter for a hundred kilometers.
most main reason the appearance of blue smoke is a large cylinder wear piston group. In this case, oil enters the cylinders through the piston rings or through gaps between the valve stems and guide bushings. Most often, cylinders have the most wear at the point where the top ring stops when the piston is in top dead point. The cylinder takes the form of an oval. This greatly impairs the operation of the rings. Although there are other situations. For example, after a long parking of the machine, corrosion can form on the cylinders and rings. Perhaps it will be cleaned off, and the details will run in again, but this will take quite a long time.
If it smokes diesel engine, this means that the diesel does not burn completely in the cylinders, but evaporates in exhaust system under high temperature. In this case, malfunctions in the equipment that is responsible for fuel injection are likely. A malfunction of one of the cylinders or a breakdown of the injection pump is also likely. If the diesel smokes blue when warmed up, then the channel candles are most likely faulty or the compression in the cylinders is very low.

Black smoke

It is they who smoke the engine when re-enriched air-fuel mixture. This indicates a malfunction in the fuel supply system. At the same time, particles of soot are noticeable in the exhaust, which remains due to incomplete combustion. combustible mixture. Along with the black smoke comes and high flow fuel, high toxicity, erratic engine operation, loss of power and starting problems. On modern injection cars re-enrichment of the air-fuel mixture occurs due to a breakdown of various sensors or leaks in the injectors.
Quite often, a diesel engine smokes like this. The reasons may be different. Possibly diesel. Bad quality. In addition, heavy contamination is likely air filter. Wear of injectors, a faulty speed controller in the fuel pump, and failure of the high-pressure fuel pump are also possible. In particular, for high-pressure fuel pumps, the constant presence of lubricant, which contains a diesel engine, is necessary. However, our gas stations do not always offer diesel High Quality. This leads to a breakdown of the high-pressure fuel pump before the allotted time.

Conclusion

To understand why the engine smokes, find out the reasons and find ways to eliminate them with proper experience, a motorist can do it himself. But if there is no confidence in your knowledge and strength, it is better to turn to highly qualified specialists.

Not really

You can often observe a scene of a similar plan - a person starts a car engine, which for a long time was motionless. And when you start up, smoke comes out of the exhaust pipe different color whole clubs. Sometimes it happens that after the engine warms up a little, the amount of smoke will decrease, and on subsequent movement it may disappear completely. However, practice shows that the appearance of smoke is direct evidence that there are problems inside the engine. That's why long parking could become a catalyst for their further development.

The color of such smoke is often either black, or white, or different shades of the two primary colors. Experienced craftsmen can pinpoint problems by seeing just the color of the smoke. Although often along with increased level smoke, you can observe other oddities in the operation of the engine. If you catch them, the probability of a correct "diagnosis" increases significantly.

In principle, there is a small list that indicates in which engine systems to look for problems:

- feed system fuel mixture;

- engine cooling system;

- problems associated with the wear of the piston group, the distribution mechanism;

- others.

Accordingly, smoke appears when foreign impurities are present in the fuel mixture, such as: coolant, oil, or due to improper combustion of the fuel. It is the incorrect characteristics of the fuel, and as a result, incorrect chemical processes in the cylinders, that lead to the appearance of uncharacteristic smoke of different colors.

But as practice shows, quite often it is impossible to immediately accurately identify the cause of the appearance of smoke. It seems that the smoke is the same color, but the reason may be different each time. This complexity is due to the fact that often due to improper operation of one of the engine systems unstable job starts to show another.

A simple example: the cooling system cannot remove the required amount of heat from the engine. Consequently, its excess begins to warm up the motor. This state of affairs leads to burning piston rings to the cylinder walls, due to which their thickness decreases and oil is ejected from the crankcase into working area piston. Oil burns - smoke appears.

Therefore, to determine the true cause, one should first, on the basis of characteristic features malfunction of one or another mechanism. These signs will be discussed below.

White smoke

Smoke of this color is considered normal for a cold engine, that is, one that was started after a long period of inactivity. The only caveat is that this is not smoke in the sense in which it is usually perceived, but water in a vaporous state.

In fact, water is part of the products left after the combustion of the fuel mixture in the cylinders. In a cold engine, steam is clearly visible, and if you look closely at the outlet of the exhaust pipe, you will soon notice how liquid water is already collected there. As the engine warms up, the amount of steam decreases. Depending on the air temperature, the steam is denser and thicker. For example, if it is -10 C outside, then thick steam will be obtained even on a well-warmed engine. At more real -20-25 C, the steam will have a bluish tint. Much depends on the humidity of the air - the higher it is, the more steam is obtained.

If it is warm outside, and the engine has gained temperature, but steam is pouring through the exhaust pipe, the cause must be sought in the coolant. It enters the cylinders and changes the composition of the fuel mixture. For example, the head gasket is leaking. In such a fuel mixture, the water content increases, and it does not burn out completely during the working cycle. If you look at the steam coming out in order to determine what is broken, you need to remember that its color depends on the lighting on the street in this moment time, composition of antifreeze with foreign impurities and weather.

A universal way to determine the presence of steam in exhaust gases is that it immediately disappears when it exits the exhaust pipe (unlike exhaust gases with a high oil content, the mass of which remains suspended in the air for a long time).

To make sure that the problem is in the coolant with all the ensuing conclusions, a series of simple tests can be carried out.

First, you need to be sure that the composition of the exhaust gases contains an increased content of water vapor, and not oil. To do this, the engine is warmed up, until it reaches its operating temperature, they take a sheet of clean paper and loosely cover the exhaust pipe with it. There should not be greasy spots on the sheet, it should not be greasy to the touch.

Secondly, you need to start looking for a place where the coolant enters the cylinders. Potential culprits are damaged gaskets or cracks in the cylinder head and in the block itself. Most main feature - traffic fumes will get into the cooling system of the car, sometimes you can find a gas plug there.

To be sure of the correctness of the cause, you need to look into the coolant reservoir. When exhaust gases enter the cooling system, their smell is immediately felt as soon as you open the cork. And an oil film will float on the surface. Plus the fluid level will drop noticeably.

An interesting feature is that the presence of exhaust gases in the cooling system changes the pressure level in it. When starting the engine, even “cold”, the pressure will increase significantly (you can squeeze the upper radiator hose and immediately feel it). It is clear that the level of antifreeze (or antifreeze) in the expansion tank will also creep up. Sometimes bubbles of exhaust gases fly out of it with a characteristic smell for them.

When the engine stops its work, the pressure inside the cooling system drops. Liquid begins to fill the cylinder. It will invariably pass through the piston rings and into the oil pan. Here it mixes with oil and forms a so-called emulsion (a mixture of oil and water). She has light color and opaque. When such a mixture circulates through the engine lubrication system, it leaves a light foam film in it. Brown. It is especially clearly visible under the oil filler cap. Easy to check - you need to look at the color of the dipstick.

If the size of the crack is small and the coolant enters the oil in small portions, the color of the oil will not change, but the foam will be necessary. It is much worse if the liquid goes in large quantities. If it gathers a lot under the cylinder, the starter will not be able to scroll crankshaft due to huge opposition. If the shaft starts to move, a water hammer will form, the connecting rod will break or bend.

It must be remembered that when coolant penetrates into the cylinder block, it cleans well everything it comes into contact with. This means that by unscrewing the spark plug, you can be surprised at its cleanliness. Sometimes, to check, the crankshaft is scrolled to such a state that both valves remain in the closed position. After the car is fixed braking system and turn on the transmission. Further, having unscrewed the candle, a hose is connected to the cylinder, through which they begin to pump air. And look at the level of antifreeze in the tank. If he starts jumping, the reason is found.

Then you only need to disassemble the engine (remove the cylinder head) to find the place where the fluid directly enters the cylinders. Special attention it is necessary to pay attention to the gaskets and the condition of the internal surfaces of the cylinders and block. It is clearly seen how the gasket and the plane of the head are deformed if it is burned out due to a violation of the heat exchange system (for example, the thermostat or fan does not work). That's when obvious traces are not visible, this makes the task difficult.

Then the parts must be checked under pressure for tightness. Typically, cracks form on the wall of the combustion chamber in the area exhaust valve. Sometimes it happens that the cylinder itself bursts. For inspection, lower the piston to the BDC position (lower dead center). The fracture point is clearly visible - the piston rings polish it, and the edges diverge into different sides. In such cases, the walls are said to breathe.

Also, liquid can enter through the injection system. Characteristics this type of failure is different from those described above. Exhaust gases do not penetrate the cooling system, no oil film is observed on the surface of the antifreeze. At the same time, its level drops, and when checking the oil, an emulsion is detected. If there are such signs, you can immediately determine the place where impurities enter the fuel mixture and do not remove the cylinder head in vain.

You also need to remember that the coolant itself under normal conditions does not enter the fuel mixture. To do this, you need the engine to constantly hold high temperature. And here the reasons should be looked for already in the cooling system. It happens that the thermostat does not perform its functions. Or a fan. Or there is a violation of the tightness of hoses, pipes, radiator, and so on.

In any case, to operate the engine with such signs means, after some time, to put the car on overhaul. By themselves, defects will not be eliminated. And the emulsion will quickly render the engine parts unusable.

blue smoke or blue smoke

The main reason for the appearance of this smoke is the presence in the fuel mixture a large number oils. This smoke has a lot of different shades(from transparent blue color to deep white-blue). There are many factors that affect color - this is the degree of warming up of the engine, and its mode of operation, and lighting, and the amount of burning oil, and others. When tested with paper, described above, characteristic oil stains remain on it.

A clear sign that oil is entering the fuel mixture is its consumption. With an engine appetite of 500 grams per 100 kilometers, smoke of a characteristic color will appear in transient operating modes. With an increase in this indicator to one liter, smoke will become a constant companion of the engine. On modern machines, however, there is a system for cleaning exhaust gases from harmful impurities in the form of a neutralizer. It can clean them even in cases where the oil consumption will reach high values.

There are only two ways for oil to enter the cylinders - through the bottom (through the gaps between the cylinder walls and piston rings, oil is taken from the oil pan) and through the top (through small gaps between the guide bushings and valve stems).

Most common cause the appearance of this type of smoke - the appearance of wear on the parts of the piston group, especially piston rings.

For example, the upper compression rings wear out in several directions: along the outer part, which has contact with the cylinder walls, and along the end part (which is affected by gases). Sometimes it happens that the grooves wear out. Then they create the so-called "pumping effect", that is, the upper rings capture the oil and supply it to the combustion chamber. This state of affairs can be observed even when oil scraper rings are operating normally.

The reason also lies in the uneven wear of the surface of the cylinders. So, the part corresponding to the stop of the rings when the piston is raised to top dead center (hereinafter referred to as “TDC”) wears out the most. Also in the middle part they sometimes take the form of an oval. Thus, gaps appear through which oil enters the combustion chamber.

Sometimes it happens that the oil contains foreign objects and due to debris (abrasive particles) due to bad work oil filter. Such objects scratch the walls of the cylinders, forming paths on them for access to the oil combustion chamber. In such cases, the rings, even in good condition help little.

If the vehicle is parked for a very long time idle engine, rust may appear on the walls of the cylinders and the surface of the rings. To restore the original state, a long period of time will be required for the mutual running-in of parts. Although, sometimes it happens that the original state cannot be restored.

Similar effects occur when the engine is not properly repaired (too rough processing of the cylinder, due to which it acquires an irregular shape) or the use of low-quality parts. Normal running-in in such conditions is impossible.

When the parts of the piston group wear out, there is a loss of compression in the cylinders, which negatively affects the development of engine power and traction properties. Compressometers or leak testers are used for checks. But there is one caveat. A large amount of oil seals the gaps well, which leads to positive instrument readings. This fact can confuse in the process of searching for the cause and send you on the wrong path.

There is one more remarkable fact. When wear has not reached high values, blue smoke appears when starting the engine and gradually disappears as the engine temperature increases. The reason is simple - the parts, when heated, expand and fit closer to each other, thus reducing the possibility of penetration of engine oil into the combustion chamber. If the gaps are large enough, the oil without any problems, due to the decrease in its viscosity through heating, enters the cylinders.

Of course, the easiest way to "decipher" faults associated with significant problems of parts. For example, frequent detonation will cause the bridges on the rings to break. Sometimes the rings themselves break.

Severe overheating causes displacements along the plane of the piston skirts, and as a result, warping and improper wear. Similar problems are possible if the connecting rod has received a water hammer (water has entered the engine). Or when the belt broke, the piston hit an open valve.

If you fill the engine with oil Low quality, it is possible that the rings stick to the piston walls. Sometimes, due to incorrect temperature distribution, complete burning of the rings is possible with the loss of any mobility.

Typically, these effects do not appear on all cylinders at the same time. To find a fault, compare the compression values \u200b\u200band the condition of the spark plugs. Often the operation of the engine is accompanied extraneous knocks and noise, especially noticeable when changing loads, speeds and the degree of warming up. It is especially noticeable when one of the cylinders is turned off and the engine starts in cold start mode.

The operation of the engine in this mode is accompanied by increased oil consumption. Quite often, the reason lies in the wear and loss of their original qualities of valve stems and valve stem seals. As the temperature rises, the oil heats up, its viscosity decreases, and it easily passes through the gaps, which causes a thick smoke effect when starting a cold unit.

In addition, oil injection is increased when running on idling and during engine braking. At times like this inside intake manifolds a vacuum is created, which contributes to the flow of oil into exhaust system and the appearance of a large amount of smoke at the first moments of launch.

If the engine is equipped with a turbocharging system, oil can get into the fuel mixture due to wear of the turbocharger parts, in particular, its bearings. Upon failure front bearing a certain amount of oil collects in the inlet pipe, and oil carbon deposits form on the candles. This malfunction is quite difficult to find, since most of the oil burns out directly in the exhaust system.

Sometimes the appearance of such smoke is facilitated by the disconnection of one of the cylinders from the work of the general group. This happens if the valves burn out or the ignition system does not work properly. Then the smoke becomes more blue-white. It is easy to find such a defect - the compression in the problem cylinder will be either weak or absent altogether. And the candles will be abundantly covered with black soot.

There are also unique cases. So, due to a rupture of the regulator membrane in an automatic transmission, the engine can take oil out of the box. It uses a vacuum to perform its functions. Near such a system are cylinders that act as a pump, pumping oil out of the box.

black smoke

The reason for the occurrence of such smoke is the incorrect operation of the fuel supply system, which re-enriches the fuel mixture. The content of soot in such smoke reaches high values.

Constant companions of this smoke are increased fuel consumption, instability of work, bad starts.

In engines using carburetors to prepare the fuel mixture, the cause should be sought in a defect in the needle valve, which becomes unusable due to the appearance of coke on the air jets. Valve failure leads to overflow in the float chamber.

When using an electronic fuel injection system, the causes of the problem are hidden in wrong work various sensors and in case of injector depressurization. With the last malfunction, a water hammer may occur - the fuel will fill the cylinder, the piston will not be able to approach the TDC and the connecting rod is deformed.

Diesel engines smoke in a similar way if the pump is not working properly. high pressure or the injection angle is too far ahead.

The distribution of fuel through the engine system is fraught with trouble. First, the parts of the piston group suffer, especially the cylinder walls. Fuel washes away oil and scuffs appear on them. The degree of wear of all parts also increases.

Secondly, when mixed with oil, the fuel changes it physical properties. It contributes to liquefaction, which leads to the accumulation of most of it in the engine crankcase. Naturally, this has an extremely negative effect on the condition of the friction surfaces of engine parts that do not receive enough oils.

Diluted oil acquires the characteristic smell of fuel. It is clear that the operation of an engine with such characteristics is a way to soon drive a car for a major overhaul.

In the practice of any motorist, there were situations when exhaust gases, their color, density, smell changed. IN soon you will have to visit a car service to find out why the engine is smoking and to diagnose the engine.

Speaking in in general terms when the engine smokes, the reasons for this, in most cases, are associated with the operation of the cylinder-piston group (hereinafter referred to as the CPG) and the ingress of foreign liquids into it, for example, oil or liquid from the cooling system (coolant), as well as the operation of the engine on a highly enriched mixture. A diesel engine smokes somewhat differently and this will be discussed below.

blue smoke

Definitely indicates the ingress of oil into the cylinders or intake tract. Such smoke does not dissipate quickly in the air, often does not disappear when warmed up, and has a characteristic smell. The reasons that the VAZ engine smokes are, most often, wear or breakage of CPG parts - violation of the cylinder mirror, wear of piston grooves, etc. For engines with a turbocharger - a malfunction of the turbine shaft seals.

Often the cause of blue smoke is the use of poor quality oil unknown manufacturers or late service engine.

With slight wear of parts, the engine smokes at start-up and stops after warming up. In this case, why the engine smokes can be explained by the expansion of heating parts and the reduction (disappearance) of the gaps between them. And vice versa - with heavily worn parts, the engine smokes at speed and hot oil penetrates into the cylinder.

Engine operation in this mode is accompanied by increased oil consumption.

If the engine emits white smoke

Often so cold engine smokes while warming up. Which is not a sign of a problem, but winter time year, it cannot be used to judge the abnormal operation of the engine. This is steam, a natural product of fuel combustion, with a decrease in temperature and an increase in air humidity, it becomes even thicker.

But if steam is noticeable in warm weather on a warm engine, then this indicates that coolant has entered the cylinders, which is often observed when the VAZ engine of old models smokes. The shade depends mainly on the amount of fluid that has entered the engine, its composition. But the main difference from blue smoke is the rapid dispersion of vapor in the air.

Basically, the engine smokes due to the ingress of coolant into the cylinders - damage to the head gasket, insufficient broaching of its fastening, or the formation of microcracks in the head or cylinder block. Such defects contribute to the entry of exhaust gases into the cooling system, which, in turn, create gas plugs in it, which is why the engine smokes and the color of the smoke is white.

It is necessary to monitor the level of the coolant, as well as its condition in the radiator and expansion tank - when opening their plugs, there should be no smell of exhaust gases and an oil film on the surface.

Diesel engine emitting black smoke

Often associated with mixture formation - this is either a lack of air or an excess of fuel. The consequence of this is increased fuel consumption, unstable engine operation modes and a drop in its power due to a suboptimal composition. working mixture. Often for this reason, a VAZ engine with a gasoline engine smokes.

The most common causes of lack of air can be a banal clogging of the air filter, air ducts, malfunctions of air flow sensors (oxygen sensor) and its circuits.

It will not be superfluous to measure the fuel pressure in the system, especially if the engine smokes heavily at high revs. If it is below normal, it is first recommended to replace fuel filters, check work fuel pump; check the integrity of the line for leaks. In this case, there is a long and untimely fuel injection. In engines with electronic injection, check the correct operation of the injectors and their cleanliness.

When a diesel engine smokes, also pay attention to the operation of the high pressure pump and the injection advance angle. In the event of a malfunction in the operation of these components and systems, black smoke may appear.

It must be borne in mind that a sharp and prolonged increase in engine load can lead to black exhaust gases.

Thus, knowing and understanding why the engine smokes, you can on your own carry out diagnostics, find and fix a malfunction, in some cases - on their own, therefore, save money on diagnostics in a car service.

Any car constantly sends exhaust gases into the atmosphere - and this is a normal situation. It's all about the amount of harmful emissions and their composition. With properly adjusted and working system gases from the muffler will be transparent and almost invisible (excluding frosty weather). But what if the engine smokes very strongly, throwing out dense exhausts of a black or bluish hue? This means that not everything is in order with your power plant and the color of the gases will help to understand the causes of the “illness” of the car.

Causes of engine smoke

The increased release of gases from the muffler may be the result of an incorrect balance between fuel and air, not simultaneous or incomplete combustion of the mixture, oil or antifreeze getting into the engine cylinders. The main reasons why a car smokes can be summarized below:

the occurrence of malfunctions in the fuel system;
wear parts cylinder-piston group;
cooling system problems;
improper functioning of the gas distribution mechanism.

Experienced car mechanics can pinpoint exactly why a car smokes a lot by examining the hue of the exhaust. And if the cause is known, then it is much easier to deal with the problem. The appearance of a bluish, white or black exhaust is often accompanied by "passing" troubles:

Difficulty starting a cold engine.
precarious work power unit at idle and under load (the tachometer needle jumps).
Increased consumption of oil and gasoline (diesel fuel).

Here it is worth making a small digression. The fact is that some cars have a relatively high oil and fuel consumption provided by manufacturers. This applies to powerful expensive cars. For example, Toyota engine 2UZ FE with a volume of 4.7 liters on the highway consumes 10 liters per 100 km, and in the city all 16. At the same time, the natural loss of oil is 1 liter per 1000 km. Such parameters are especially striking after transplanting from economical middle-class cars.

Loss of traction power of the vehicle.

It also happens that the smoke from the muffler pipe is the only sign of a malfunction of any part of the machine. You can more accurately diagnose a malfunction by the color of the exhaust.

transparent smoke

Inexperienced car owners sometimes take the steam coming out of the muffler for smoke and start to panic. However, this is quite normal. The liquid condenses on the exhaust pipe at low temperatures and after the engine starts, the water begins to actively evaporate, turning into steam. When the motor warms up to operating temperature, the "phenomenon" will stop. The amount of steam released is related to the humidity of the surrounding air: the higher it is, the longer the white "smoke". It is not a sign of a breakdown of the power unit, and no action is required in this case. To finally make sure that the engine is working properly and steam is coming out of the pipe, attach a clean piece of paper to the muffler pipe for a few seconds: the water will dry and leave no traces. If so, then everything is in order.

Black smoke exit

This trouble causes the most serious damage to the environmental situation and indicates serious problems in the power plant. There is a strong smell burnt oil or metal, the cabin sometimes stinks of heated plastic. Why is this happening? Probable causes when the engine smokes in this "mode":

malfunctions fuel system, : the composition of the air-fuel system is seriously unbalanced - an excessively enriched mixture enters the cylinders (a lot of gasoline or diesel fuel and little air);
failures in electronic unit engine management (correct injection is broken);
loss of nozzles (they overflow) tightness in injection engine;
a drop in compression in the cylinders of the power unit: the cause is the wear of the rings, pistons as a result long-term operation or poor repair.

These faults lead to increased consumption fuel, next to the machine there will be a smell of gasoline or diesel fuel. For a quick check, remove the spark plugs and evaluate them: a black coating confirms a malfunction in the ignition or fuel supply system.

Blue smoke

If it appears in a diesel or gasoline-powered car, then this indicates the penetration of oil into the cylinders. As a result lubricant composition burns, forming gray clouds of smoke, which is poorly dissipated. The blue tint can have a different intensity, which is associated with the brand of oil used, the ambient temperature. Make sure you overspend lubricant can be measured with a dipstick. A regular decrease in the amount of oil indicates its combustion or leakage. Another test is carried out using a sheet of clean paper attached to the muffler pipe with the engine running. Oily spots will only confirm the presence of a lubricant in the combustion chamber. Reasons why the engine smokes:

breakage, wear or low quality of valve stem seals: when starting the engine on a “cold” after a long stop, the lubricant composition will burn out along with the fuel, which will immediately show smoke formation;
occurrence of piston rings;
- the use of a lubricant that does not meet the requirements of the manufacturer.

Blue smoke can also form with slight engine wear. After warming up, the elements of the power unit begin to expand, and the blue exhaust gradually becomes less strong, and then may disappear altogether.

White dense smoke

It differs from steam not only increased density. If the car smokes white smoke, then the latter will dissipate for a long time. At the same time, a burning smell is felt, which does not disappear after the engine reaches operating temperature. When starting the engine on a "hot" problem is also not solved. White smoke indicates serious problems in the cooling system: antifreeze getting into the oil. Exhaust shades depend on the type of antifreeze (coolant). Reasons for this problem:

violation of the tightness of the cylinder head: the formation of cracks, severe deformation or burnout of the gasket;
the use of low-quality coolant and: poor antifreeze can literally “eat through” the metal, sharply increasing corrosion, which can lead to the impossibility of restoring some parts of the cooling system.

When mixing antifreeze and oil, the latter loses its qualities and becomes less viscous, which adversely affects the normal functioning of all systems power plant and leads to a decrease in its operational life.

What to do if white dense smoke appears

First, carefully inspect the candles: if they have scale, this indicates water has entered the cylinders. Then open the cap of the expansion tank of the cooling system: a low level of antifreeze, an oil film, a burning smell indicate a violation of the tightness of the cooling system. Next, you need to dismantle the head and check the integrity of its gasket, the presence of cracks. All restoration work must be carried out in a specialized workshop.

Actions in the event of blue smoke

Into the cooking chamber air-fuel mixture, oil penetrates through a valve that has lost its tightness or “thanks to” worn piston rings and. Then you need to bore and honing the cylinders, move on to the next repair size. Sometimes (but not for long) it helps to replace the piston rings. The first option, when the amount of oil entering the cylinders exceeds all limits, implies either valves.

Sometimes whitish smoke blue tint is formed due to leakage of the lubricant and its ingress onto the exhaust manifold. Then check and, if necessary, install new gaskets and (or) the crankshaft oil seal.

Malfunctions of the engine with a turbocharger

If the machine is equipped with this unit, then the appearance of a white exhaust with a bluish tint may be due to an oil leak, which, instead of lubricating the turbine bearings, goes into the starting system. To check this, remove the turbo from a diesel or gasoline engine and see if there is oil in the air duct. If this is the case, then it is better to visit a car repair shop. When black smoke comes out of the pipe, test the tightness of the intake system. The exit of dark exhaust during regassing is especially noticeable.

Any car constantly sends exhaust gases into the atmosphere - and this is a normal situation. It's all about the amount of harmful emissions and their composition. With a properly adjusted and serviceable system, the gases from the muffler will be transparent and almost invisible (except in frosty weather). But what if the engine smokes very strongly, throwing out dense exhausts of a black or bluish hue? This means that not everything is in order with your power plant and the color of the gases will help to understand the causes of the “illness” of the car.

Causes of engine smoke

the occurrence of malfunctions in the fuel system;
wear of parts of the cylinder-piston group;
cooling system problems;
improper functioning of the gas distribution mechanism.

Difficulty starting a cold engine.
Unstable operation of the power unit in idle mode and under load (the tachometer needle jumps).
Increased consumption of oil and gasoline (diesel fuel).

Here it is worth making a small digression. The fact is that some cars have a relatively high oil and fuel consumption provided by manufacturers. This applies to powerful and expensive machines. For example, a 4.7-liter Toyota 2UZ FE engine consumes 10 liters per 100 km on the highway, and all 16 in the city. At the same time, natural oil waste is 1 liter per 1000 km. Such parameters are especially striking after transplanting from economical middle-class cars.

Loss of traction power of the vehicle.

It also happens that the smoke from the muffler pipe is the only sign of a malfunction of any part of the machine. You can more accurately diagnose a malfunction by the color of the exhaust.

transparent smoke

Black smoke exit

This trouble causes the most serious damage to the environmental situation and indicates serious problems in the power plant. At the same time, there is a strong smell of burnt oil or metal, sometimes it stinks of heated plastic in the cabin. Why is this happening? Probable causes when the engine smokes in this "mode":

fuel system malfunctions: the composition of the air-fuel system is seriously unbalanced - an excessively enriched mixture enters the cylinders (a lot of gasoline or diesel fuel and little air);
malfunctions in the electronic engine control unit (correct injection is broken);
loss of injectors (they overflow) tightness in the injection engine;
a drop in compression in the cylinders of the power unit: the cause is the wear of the rings, pistons as a result of long-term operation or poor-quality repairs.

These malfunctions lead to increased fuel consumption, next to the car there will be a smell of gasoline or diesel fuel. For a quick check, remove the spark plugs and evaluate them: a black coating confirms a malfunction in the ignition or fuel supply system.

Blue smoke

If it appears in a diesel or gasoline-powered car, then this indicates the penetration of oil into the cylinders. As a result, the lubricant composition burns out, forming bluish clouds of smoke, which are poorly dissipated. The blue tint can have a different intensity, which is associated with the brand of oil used, the ambient temperature. You can make sure that the lubricant is overused by measuring its level with a dipstick. A regular decrease in the amount of oil indicates its combustion or leakage. Another test is carried out using a sheet of clean paper attached to the muffler pipe with the engine running. Oily spots will only confirm the presence of a lubricant in the combustion chamber. Reasons why the engine smokes:

breakage, wear or low quality of valve stem seals: when starting the engine on a “cold” after a long stop, the lubricant composition will burn out along with the fuel, which will immediately show smoke formation;
occurrence of piston rings;
- the use of a lubricant that does not meet the requirements of the manufacturer.

White dense smoke

It differs from steam not only in its increased density. If the car smokes white smoke, then the latter will dissipate for a long time. At the same time, a burning smell is felt, which does not disappear after the engine reaches operating temperature. When starting the engine on a "hot" problem is also not solved. White smoke indicates the presence of serious problems in the cooling system: antifreeze getting into the oil. Exhaust shades depend on the type of antifreeze (coolant). Reasons for this problem:

violation of the tightness of the cylinder head: the formation of cracks, severe deformation or burnout of the gasket;
the use of low-quality coolant and: poor antifreeze can literally “eat through” the metal, sharply increasing corrosion, which can lead to the impossibility of restoring some parts of the cooling system.

When antifreeze and oil are mixed, the latter loses its qualities and becomes less viscous, which adversely affects the normal functioning of all power plant systems and leads to a decrease in its operational life.

What to do if white dense smoke appears

Actions in the event of blue smoke

Oil penetrates into the chamber where the air-fuel mixture is prepared through a valve that has lost its tightness or “thanks to” worn piston rings and. Then you need to bore and honing the cylinders, move on to the next repair size. Sometimes (but not for long) it helps to replace the piston rings. The first option, when the amount of oil entering the cylinders exceeds all limits, implies either valves.

Sometimes whitish blue smoke is formed due to leakage of the lubricant and its contact with the exhaust manifold. Then check and, if necessary, install new gaskets and (or) the crankshaft oil seal.