Familiar picture: launched the engine after a long parking lot and from exhaust pipe Thought the thick smoke. It is possible that after warming up it will decrease, and when traveling and disappears at all. But more often it happens otherwise. The smoke continues and explicitly shows that there are any problems in the engine. Long inaction served as a pushing to their sharp manifestation.
Smoke from the exhaust pipe is also white, and black, and any intermediate shades. Color serves as an important diagnostic sign. The operation of an enhancement engine is often accompanied by other deviations from the norm, although sometimes poorly notable. They must be captured and celebrated to accurately assess the situation.
Usually the appearance of smoke is associated with faults of the following engine working bodies: control systems (mainly fuel feed), cooling systems, mechanical part (piston group, distribution mechanism, etc.). In accordance with this smoke, either due to incomplete or "incorrect" fuel combustion, or to enter the coolant into cylinders, or income there oil. The presence of oil, coolant or ease of fuel during combustion in the cylinders and gives the characteristic color of exhaust gases.
If you analyze possible malfunctions, it turns out that in many situations smoke the same color, although it has a different nature. Another circumstance: Often, a malfunction of one system that has a source of smoke occurs due to problems and defects in another. Here is a characteristic example: the poor work of the cooling system leads to the engine overheating and, accordingly, the burning of the piston rings. Already as a result, oil falls into the cylinders and causes smoking, the cause of which is essentially secondary.
Start the search for the cause of smoke is better with comparison of all recorded circumstances: the nature of the smallests, seen related phenomena, possible external influences. We are talking about the characteristic combinations of these factors.

White smoke.

White smoke from the exhaust pipe is quite a normal phenomenon for the warm engine warming modes. Only it is not smoke, but couples. Water in a vapor state is a natural fuel combustion product. In the untenaled exhaust system, this pair is partially condensed and becomes visible, and water usually appears on the cutting section of the exhaust pipe. As the system warms the condensation decreases. The colder environment, the more dense and white there are steam. At temperatures below -100, a white pair is formed on a well-haired engine, and when frost is minus 20-25 degrees, a thick white color becomes with a sizem. On the color and saturation of the pair also affects the humidity of the air: the more it is more, the pairs are thick.
White smoke in warmth time and on a well-haired engine is most often associated with the getting of coolant into the cylinders (for example, through a non-grinding of the block head). The water contained in the coolant does not have time to completely evaporate when combustion of fuel and forms a rather thick white smoke (in fact, steam again). Its shade depends on the coolant composition, weather and illumination on the street. Sometimes he looks like a Sizem, reminding "oil" smoke. It is easy to distinguish water vapor: it immediately dissipates, and after the "oil" smoke in the air remains a bluish fog.
To make sure that the cooling system is required, a number of targeted checks will be required. It is easy to clarify that water is really thrown out of the exhaust pipe, and not oil. To do this, on a well-haired engine briefly closed the hole of the exhaust pipe with a sheet of paper. Drops of water from the leaf will gradually evaporate and will not leave obvious fat traces, and they will not be fat to the touch.
Further search must be coordinated with the engine design. The liquid can fall into the cylinder due to not only damage to the gasket, but also cracks in the head or block of cylinders. All these defects when working the engine causes exhaust gases In the cooling system (sometimes a gas plug is even formed there), which serves as the basis for recognition.
Opening the radiator cork or the expansion tank, it is easy to notice the smell of exhaust gases and the oil film on the surface of the coolant. Yes, the level of fluid will be reduced. It is characteristic that in such cases, after starting the cold engine, the pressure in the cooling system immediately increases (it is not difficult to feel your hand, compressing the upper radiator hose), the fluid level in expansion tank. Moreover, this level is unstable and in the tank one can notice the output of gas bubbles, sometimes with a periodic release of coolant from the tank.
If the engine stop, then the picture will change. The liquid begins to go into the cylinder. Gradually it passes through piston rings And enters the oil, in the pallet of the crankcase. With the subsequent launch, the oil with liquid is mixed, forms an emulsion and changes the color - becomes opaque and lighter. Circulating over the lubrication system, such an emulsion leaves on the cover of the head and a plug of oil-coaling neck a characteristic foam of light yellow-brown.
This is checked by drowing the oil probe and opening the neck plug, but if the defect (crack, squeak) is small, then no changes may not be (it happens that the oil remains clean, although the foam is formed). On the contrary, if the leakage in the cylinder is essential, then the liquid, accumulating over the piston, even prevents the burden crankshaft The start at the first moment when starting. In particularly severe cases, it is possible to hydrate in the cylinder, deformation and breakage of the connecting rod.
Sometimes it is possible to clarify the place of the defect. Finding into the cylinder, the coolant is actively "cleans" everything, with which it comes into contacts, so the ignition candle will look completely fresh. If, through the candle hole, use air under pressure in the cylinder (for example, through an adapter with a hose or a special leakage tester), the level of fluid in the expansion tank will begin to increase (when checking, it is necessary to rotate the crankshaft to a position at which both valves are closed, put a car on brake and turn on the transmission).
Further checks are possible only with a disclosed block of block. Assess the state of the gasket, the planes of the head and block. The starting of the gasket is often accompanied by the deformation of the head plane, especially if the defect preceded the engine overheating (for example, due to the thermostat fault, fan and other reasons). Worse, if obvious defects were not found. Then it is necessary to check the head on pressure tightness; It is most likely that a crack will be detected on the wall of the combustion chamber (more often near the exhaust valve seat). You should also carefully examine the cylinder, lowering the piston into the lower dead point. The crack in the cylinder is a rare defect, but if it is, it is easy to detect it. The edges of the crack diverge (the walls "breathe") and often turn out to be polished piston rings.
It also happens that the cooling fluid enters the cylinder through the inlet system - for example, due to the leakage of the intake manifold laying (if it simultaneously compacts the coolant coolant collector coolant. In such cases, the pressure in the cooling system does not increase, the smell of exhaust gases is not in it, but the oil turns into an emulsion, and the coolant level is rapidly decreasing. These signs are usually enough to find a defect and not confuse it with the above-described, otherwise the block head will be removed in vain.
All problems associated with white smoke from the exhaust pipe require not only eliminating direct causes. Since defects are usually caused by engine overheating, then check and eliminate malfunctions in the cooling system - it is possible that the thermostat does not work, the switching sensor, the coupling or the fan itself, a non-grinding radiator, its plug, hoses, or connections.
If the white smoke and the accompanying defects are noticed, then the car cannot be operated. First, defects quickly progress. And secondly, the operation of the engine on the water-oil emulsion sharply accelerates the wear of parts and after several hundred kilometers without major repairs, most likely, not to do.

Blue or SIZY smoke

The main reason for the appearance blue smoke - Eating oil into the engine cylinders. The "oil" smoke can have different shades - from a transparent blue to thick white-blue, which depends on the mode of operation of the engine, the degree of its warm-up and the amount of oil entering the cylinders, as well as illumination and other factors. It is characteristic that the oil smoke, in contrast to the steam, does not dissipate in the air quickly, and the above-mentioned test with paper gives fatty drops, flying out of the pipe along with exhaust gases.
It is also obvious that the oil smoke is accompanied by increased oil consumption. Thus, at a flow rate of about 0.5 l / 100 km, the SIZY smoke appears mainly in transient modes, and when 1.0 l / 100 km is reached on the modes of uniform movement. By the way, in the latter case, in the transitional modes, the oil smoke becomes dense blue-white. True, owners of the most modern machines It is necessary to remember the possible presence of a neutralizer, which is capable of cleaning exhaust gases from oil even with sufficiently large expenditures.
The oil in the cylinders (more precisely, in the combustion chamber) falls in two ways - either from the bottom, through the piston rings, or on top, through the gaps between the rods of the valves and the guide bushings.
The wear of the details of the cylinder-piston group is one of the most common causes of the appearance of oil smoke. In the upper compression rings, wear is observed not only on the outer surface in contact with the cylinder, but also by the end planes that perceives the pressure of gases in the cylinder. Can be worn and grooves of these rings in pistons. Large gaps in grooves create a pumping effect. Even if the oil lifting rings are still normal, the oil still enters the cylinders, since the upper rings continuously "pump up" from the bottom up.
Cylinders are most weathered in the zone of stopping the upper ring at the position of the piston in top dead The point, and in the middle part there is often an oval shape. The deviation of the shape of the cylinder from the circle worsens the sealing properties of the rings. In the zone of locks, lumens are usually formed, but their appearance is not excluded in other places of the circle.
There are often cases when, with a relatively decent state of the rings and pistons, the surface of the cylinder is damaged. This happens, for example, with poor oil filtration, when abrasive particles fall between the piston skirt and the cylinder. Then the cylinder arises scratches.
A similar situation is real and after a long parking lot, when corrosion foci may appear on the surface of the cylinders and rings. It will take considerable time to smooth out these defects and mutual acquisition of details (if they can work at all).
The same effect often occurs when the engine repair technology is impaired, if the surface of the repaired cylinder is too coarse or the cylinder is irregular, or low-quality pistons and piston rings are used. In such cases, as a rule, it is generally impossible to count on a normal acquisition.
The wear of the details of the cylinder-piston group are often accompanied by a compression loss and an increase in the pressure of crankcase gases, which is determined by the appropriate devices (compressometer, leakage tester, etc.). However, it should be remembered that a large amount of oil entering the cylinders is well compacted by the gaps in conjugate details. If they are not too high, then the result of the compression assessment can be quite normal, sometimes even closer to the upper limit. This circumstance confuses the search for a specific reason for the blue oil smoke.
Another note on the characteristic circumstances. When there are no large wear of parts, then blue or blue-white smoke is clearly observed only when driving the engine, gradually decreasing and even disappearing. The reason is simple: heating, the details acquire the form and occupy the place at which they are better adjacent to each other. With excessively large wear, the picture is inverse: smoke on a warm engine will increase, as it is easier to get hot oil, having a low viscosity, it is easier to get into the cylinder through worn items.
It is always easier to determine the malfunction associated with more serious defects or even breakdowns of parts. So, detonation usually leads to a breakage of the jumpers between the rings on the pistons, less often - to the breakage of the rings themselves. Strong engine overheating causes deformation of the piston skirts, a large gap between the piston and the cylinder is formed. The deformed piston is thrown by breaking the rings. The same result is possible during the deformation of the connecting rod, for example, due to the hydroudar when water in the cylinder, or after breaking the belt and the piston impact on the uncrowel valve.
The use of low-quality oil can cause burning and running rings in piston grooves. And due to the long-term vibil ignition, the ring can be simply fledged in grooves with full loss of mobility.
The defects considered above are usually not in all cylinders immediately. Find a faulty cylinder is not difficult, comparing the state of the spark plugs and the value of the compression in different cylinders. Moreover, such defects often accompany different types of extraneous noises and knocks, changing with turns, load and degree of engine warming, as well as the unstable operation of the engine due to the disconnection of the cylinders (especially when cold start).
A common group of faults causing oil smoke and oil consumption is associated with wear of the rods of valves and guide sleeves, as well as wear, mechanical defects and aging (loss of elasticity) of oil-challenged caps. These defects, as a rule, give a noticeable increase in engine chimney as heated, because the dischargeable hot oil is much easier passed through the gaps between the worn items. In addition, oil entering the cylinders is enhanced by idling And when braking the engine. In these modes in the intake manifold, a large vacuum occurs, and oil flows over the rods of valves under the action of pressure drop, accumulating on the walls of the parts and in exhaust system. Subsequent opening throttle valve At the first moment sharply enhances the thickness of blue oil smoke.
In engines with turbocharged oil consumption, accompanied by blue smoke, is possible due to a turbocharger malfunction, in particular, the wear of bearings and the rotor seals. Worn sealing front bearing The compressor gives a picture similar to the failure of the oil-challenge cap (including oil nagar on the candlelight), but at the same time the oil puddle is collected in the compressor's inlet nozzle. Malfunction of the sealing turbine is difficult to determine because the oil comes directly into the exhaust system and goes there.
In operation, the blue smoke and oil consumption often appear when one of the cylinders is disconnected due to the malfunction of the ignition or with the valve leaks. In the latter case, smoke becomes white-blue, especially if the valve has an explicit mark. Such a defect is determined without difficulty - compression in this cylinder is insignificant or absent at all, and abundant black Nagar appears on the candle, often in the form of growths.
There are also quite exotic defects that cause blue oil smoke. So, U. automatic boxes Transmission with a vacuum load sensor is possible to break the regulator membrane. Since its cavity is connected by a hose with an intake manifold, the engine begins simply sucking the oil from the gearbox. As a rule, the oil comes only in those cylinders, about which the selection of vacuum is taken in the collector. At the same time, it is possible to cast candles and splashing oil from candle holes (we will remind that oil ATF. usually have
Red color).

Black smoke

The black smoke from the exhaust pipe indicates the re-enters the fuel-air mixture, and, consequently, about the faults of the fuel-feed system. Such smoke is usually clearly visible on a light background for the car and is particles of soot - the products of incomplete combustion of fuel.
Black smoke is often accompanied by a large fuel consumption, poor launch, unstable engine operation, high toxicity of exhaust gases, and often loss of power due to the non-optimal composition of the fuel and air mixture.
In carburetor engines, the black smoke usually occurs due to overflow in the float chamber due to the defect of the needle valve or due to the location of the air jets.
In gasoline engines with electronic fuel injection, the reobey of the mixture appears, as a rule, when malfunction and failures of various sensors (oxygen, air flow, etc.), as well as with nozzles of nozzles. The last case is danted by a hydroudar in the cylinder when starting with all the consequences mentioned above. The point is that through a faulty nozzle on a non-working engine in a cylinder can find a lot of fuel, and it will not allow the piston to approach the top dead point. Diesels black smoke sometimes appears not only with violations in the pump high pressure, but also with a large insertion angle of injection.
Common for the operating modes of gasoline engines on a re-engaged mixture is increased wear and even the styles of the cylinder-piston group, since excess fuel is flushes oil from the cylinder walls and worsens the lubricant. In addition, fuel enters the oil and dilutes it, worsening the lubrication conditions and in other conjugate engine parts. In some cases, this discharge is so large that the oil level in the crankcase (more precisely, the mixture of oil with fuel) is significantly increased. Diluted oil acquires a distinct smell of gasoline. Obviously, the operation of the engine with such faults is not only difficult, but also extremely undesirable, since it quickly leads to new, much more serious trouble.