White soot on all VAZ 2109 spark plugs means a problem with the ignition system

Causes of soot

The causes of black spark plugs must first be identified. There can be several situations: all candles are exposed to attack or only one. Another sign is that the part is blackened on only one side. The degree and intensity of soot formation depends on a number of parameters, namely:

• Plaque formation on a new spark plug occurs after 200-300 kilometers of driving. It is recommended to drive as evenly as possible, avoiding an aggressive driving style, in order to objectively assess the condition of the components.
• The volume and color of soot is directly affected by the quality of the fuel. If, in parallel with the breakdown, you use low-quality gasoline, it will be problematic to determine the cause by the color of the soot.
• Incorrectly set idle speed in a carburetor car also affects the soot parameters.

Let's move on to the reasons for the appearance of soot. We have provided the most complete list for drivers:

• The appearance of carbon deposits is only on one side. The cause here is a burnt valve. Plaque forms on the spark plug from below at the side electrode.
• The candle has an incorrect heat rating. If it is less than necessary, you will notice changes in the shape of the soot cone; if the parameter is larger, then only the upper part will be black.
• Uniform black deposits throughout the part. The reason is late ignition.
• Black carbon deposits on the injector spark plugs. Here, incorrect operation of the sensor (air flow), depressurization of the injectors (fuel entering the cylinder even with the injectors closed) is possible. Also, incorrect carburetor adjustment causes excessive deposits on the spark plugs.
• Black carbon deposits on the carburetor spark plugs may indicate breakdown or wear of the power mode economizer components.
• Worn or completely clogged air filter.
• Malfunctions in the ignition system. Here it is worth checking the ignition angle, high-voltage lines, distributor, and coil.
• Damage to the fuel regulator.
• Insufficient compression level in a certain cylinder.
• Black plaque can be different, which we will talk about later.

Oily black soot

It is easy to detect, as the coating has a characteristic shine like oil. If you are faced with this particular type, we recommend that you first check the elements of the cylinder-piston group:

• piston rings;
• valve stem seals;
• valve guides.

It is recommended to replace worn parts.

Black velvety matte

As a rule, such deposits are formed due to the ingress of a mixture too rich in gasoline into the cylinder. When diagnosing, you should start checking with the following components:

• spark plugs directly (make sure they are compatible with your engine);
• checking the set carburetor parameters;
• air filter.

This is the main list of reasons for the appearance of black carbon deposits. As you can see, plaque of this color is the most common, so diagnosing the cause is the most difficult. With “colored” carbon deposits the situation is a little simpler.

Red soot

The red color may be due to manganese or lead. These substances are contained in a variety of additives. If the driver overuses them, it is recommended to eliminate or reduce their use. Car owners should replace the spark plugs and liquid (oil or fuel) to which the additive was added when carbon deposits are detected.

White soot

Similar to black, several types of white plaque can be visually distinguished, which will be discussed below.

Glossy white

If such deposits are detected, you should urgently address the problem. He talks about exposure to high temperatures. Both the spark plug and the engine components can overheat. The cause of overheating is incorrect operation of the cooling system. Additional reasons may be:

• lean fuel mixture;
• air leak;
• incorrectly configured ignition;
• use of unsuitable spark plugs in the engine.

Faint white

The problem lies in the fuel. For diagnostics, we recommend cleaning the spark plugs and adding another fuel (of better quality). In most situations, switching to a different gasoline solves the problem.

Video about diagnosing spark plugs by their soot

The presence of black carbon deposits on the spark plugs should alert the car owner. This phenomenon is not typical for a working engine, which means that some of its systems have malfunctioned.

As a rule, these are: ignition systems (carburetor), power supply (injector), fuel, lubrication, and malfunctions in the gas distribution and crank mechanisms may also occur.

Despite the fact that blackening of spark plugs can be caused by many reasons, diagnosing them is not as difficult as it seems at first glance. This is what we will talk about in this article.

What to do if soot appears

Once you have found carbon deposits on your spark plugs, try to identify its color and type according to the information provided above. This will help roughly identify the source of the problem. Even if you have never had your car repaired, do not rush to contact a car service center. In order not to look like an ignorant driver, and to avoid being deceived by mechanics, we recommend trying to diagnose the source of carbon deposits yourself. If carbon deposits appear on only one spark plug, swap dirty and clean spark plugs. The problem is practically identified when carbon deposits appear on a clean spark plug. Here the issue is in the cylinder itself. When plaque appears on each of the candles, of course, focus on the color and nature of the deposit. Some problems can be solved by simply changing the fuel or air filter. If you intend to work with components of the cylinder-piston group, we recommend contacting a specialized technical center. Do not neglect the service if overheating of the spark plugs is detected. This problem may lead to the need for major repairs, the cost of which will significantly empty your wallet.

Varieties of black soot

The black color indicates the presence of ordinary soot on the candle, that is, unburned amorphous carbon. It is produced by petroleum products and other organic matter that have failed to oxidize properly.

A more accurate assessment of the situation is determined by both the shades of color and the nature of its distribution over the working part of the candle. The appearance of any belts around the outer part of the insulator, located above the hexagon under the spark plug wrench, is usually not a cause for concern, although many auto repairmen mercilessly reject good spark plugs for this very reason. At the very least, this is not justified.

• Uniformity of carbon deposits. It can be concentrated only on the metal of the electrodes, lie on the insulator on one side, or have a location in the form of a cone going deep into the body. As if revealing the source of its appearance in the form of uneven carbon flow or temperature changes along the insulator.

• External dryness of soot. It may look slightly damp and even have a different smell, for example, a strong smell of gasoline. There should be no gasoline remaining in a properly functioning cylinder.

• Oiliness. The porous carbon structure is easily impregnated with oil, and is often formed from it. There are always oil vapors in the combustion chamber, but normally their amount is negligible, and they burn out instantly.

• “Velvet” type of soot. This indicates its large-pore structure, that is, rapid formation and increase in volume.

• The opposite situation is a dense, even possibly shiny deposit. It accumulates for a long time, is durable and does not have a radical black tint.

• Combination of black with other colors. For example, red or brown.

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Such nuances indicate various causes of problems. If you rely on them when diagnosing, you need to make sure that the formations are stable and did not accidentally appear a minute ago. To do this, the engine must at least be warmed up, or better yet, loaded with tens of kilometers of movement at a fairly high speed.

The nature of the deposit will tell you about the causes of malfunctions

The shade of soot on the electrodes of the elements is a clear signal of what kind of failures in the power unit could lead to this. This is often due to the fact that sparking does not occur correctly, the composition of the fuel used or the temperature indicator inside the combustion chamber does not meet the requirements. We will tell you why the candles turn black later.

Oil deposits

If you do self-diagnosis, it is easier to determine the source of the problem in individual cases. Black oily candles are one such situation. Characteristic symptoms are also:

• problematic engine starting;
• misfires of certain cylinders;
• twitching and “sneezing” of the engine;
• bluish smoke from the exhaust pipe.

If all this is observed in your car, it means that oil has gotten into the cylinder. If it comes through the bottom, then the problem is in the piston rings. The driver will need an engine rebuild or a complete overhaul. Oil can also come from the cylinder head through the top. The solution is simple and inexpensive - replacing the valve stem seals. The procedure is simple, so drivers can try to replace these parts themselves in the garage.

Origin of red plaque

When diagnosing spark plugs, many car enthusiasts expect to see black resinous deposits, soot or something worse, but in 20% of cases the deposits can be white. White deposits on the spark plugs indicate problems with fuel quality and a significant decrease in fuel in the combustion mixture; if the white deposit is a little rough to the touch, if the deposit is glossy, the cause is frequent overheating of the engine.

• Provided that the spark plug is not suitable for this type of engine;
• The inlet pipeline is depressurized, which is why air is often taken in from outside;
• Problems with the cooling system, most often due to untimely replacement of the cooling element;
• Problems with the radiator;
• Poor ignition calibration.

Quite often it happens that the surface does not have a white coating, but a slightly yellowish one, which is typical for problems with an increase in temperature in the combustion chamber when the engine is running at maximum speed. To prevent overheating, you should change gears before the engine reaches 4,000-5,000 rpm.

A yellow coating on the spark plug may be the result of problems with insufficient fuel in the combustion mixture; yellowing of the insulator indicates that the fuel is highly enriched in lead, in this case it is better to change the fuel, engine oil, flush the fuel system and install new spark plugs.

This phenomenon is less common than the effects described above. Why are there red electrodes on some spark plugs?

• the tank is filled with low quality gasoline with additives that increase the octane number;
• a car enthusiast or a fuel supplier adds additives to gasoline, which contain a large amount of metals;
• the owner of the car installed spark plugs in the cylinders that did not match the heat rating.

The reasons for the reddish tint of spark plugs do not pose a direct threat to the power unit, but are harmful in the long term. Driving on low-quality gasoline with unknown additives a priori accelerates the wear of parts and components. Plus an increase in consumption arising from worsening combustion conditions of the mixture in the cylinders.

Operating a car with spark plugs that are “cooler” or “hotter” in terms of heat rating reduces engine power and significantly shortens the life of the elements. A characteristic sign of incorrectly selected spark plugs is a drop in crankshaft speed at idle and missed ignition cycles.

The gradation of electrode colors from light gray to white (light yellow is also possible) is evidence that the engine is running on a lean mixture. Related reasons may be:

• The product is too hot. The heat rating of the product is lower than that recommended by the manufacturer.
• Large ignition timing angle.
• Using low octane gasoline.

There is no point in delaying in finding out the circumstances that caused this soot-colored condition on the new spark plug. A lean mixture directly causes overheating of both the igniter and the combustion chamber. Ultimately, this situation can lead to burnout of the exhaust valves.

When analyzing the factors that caused a poor quality mixture, it is useful to check for the presence of abnormal glow ignition. A symptom indicating its presence is the reluctance of the engine to stall when the ignition is turned off. In total, this means that the “match” was not created for this engine.

Deposits on the insulator

Drivers often encounter an effect called “triple motion”. It means that one of the cylinders (or several) is inoperative. The term originated at a time when four-cylinder engines were widely used. When only three of the 4 cylinders were working, the term “troit” appeared. In such a situation, a characteristic feature is carbon deposits on the insulator. It is necessary to clean the spark plugs or install new ones. If the “triple” of the motor does not disappear, more detailed diagnostics from specialists is necessary.

How to get rid of black plaque?

Oil on spark-forming elements harms the ignition system. An oily film provokes overheating and the appearance of soot, which can result in complete breakdown of the electrodes. The candles will have to be thrown away.

If only one element has turned black, you can determine the malfunction by swapping it with a normal spark plug. If a serviceable element also turns black, it means that the spark generators have nothing to do with it - the fault should be looked for in the cylinder. Accordingly, if no changes occur, the candle is “to blame.”

It is necessary to regularly check the spark-producing elements and also clean them. Experts advise doing this every 10,000 km or at the next oil change. Some drivers clean with sandpaper, but this can damage the protective layer (especially in iridium spark plugs).

For cleaning you will need the following materials:

• synthetic detergent;
• disposable plastic cups (must be disposed of immediately after use);
• a fuzzy cleaning device (such as a toothbrush);
• rags.

Pour the cleaning agent into a plastic cup prepared in advance. Any surfactant will do. We fill the glass with it to such a level that the electrode part of the candle along with the threaded connection is immersed in the detergent. The elements should remain in this position for at least half an hour, but their stay in the solution can be extended to 45 minutes. At this time, a chemical reaction will occur - you can observe the process of purification of the elements.

Then we take the candles out of the glass and clean them with a brush - the electrode is the most diligent. Then wash the elements in warm, preferably running water. Finally, wipe them dry with a rag.

The final stage is drying the elements. In winter, a home heating radiator is suitable. You can also use a hairdryer, fan heater or oven. The temperature in the oven should not exceed 70 degrees.

The main thing is to achieve complete evaporation of moisture from the surface of the element. During the procedure, all dirt on the surface must be removed. A clean spark plug will work much more efficiently than a dirty spark plug, which means the efficiency of the entire power unit will increase.

The appearance of soot on the spark-forming elements of carburetor and injection engines can occur for various reasons (incorrectly selected elements, prolonged driving at high speeds, etc.). To prevent the appearance of carbon deposits, they need to be checked periodically - it is advisable to do this at the next oil change. Clean spark plugs and the correct gap on them are a guarantee of trouble-free engine operation.

Any driver knows that without spark plugs, a gasoline engine cannot operate. The VAZ-2107 car is available in modifications only with gasoline engines, so spark plugs are installed on all “Seven” models. Since the VAZ-2107 has a four-cylinder system, there are therefore four spark-creating devices in the car. Failure of at least one of them leads to abnormal engine operation, which manifests itself in the form of “triples”, a decrease in power, a slow increase in speed, breakdowns, “jerky” movements, and rapid heating of the engine. These are the consequences of only one spark plug failing, and the more of them that don’t work, the more critical and dangerous it is for the “seven” engine. The most dangerous thing is overheating of the engine, as a result of which the rings and pistons can “burn”. Repairs including replacement of rings will cost a decent amount, so it is easier to prevent the engine from operating with prolonged critical overheating. There are many reasons for overheating, but this article is devoted specifically to the problems of spark plugs.

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Cleaning spark plugs from carbon deposits

The appearance of carbon deposits requires the driver not only to consider the cause and remove it, but also to clean the spark plugs if they are to be used further. Plaque will appear in any case, so it is recommended that motorists inspect spark plugs every 10 thousand kilometers. We recommend carrying out an inspection in conjunction with an oil change. If the symptoms described above are detected, inspection of the candles should be done out of turn. Some drivers use the “old-fashioned” method (sandpaper) for cleaning. It is highly not recommended to clean electrodes using this method. Modern candles have a thin protective layer that will quickly wear off. This especially happens in iridium products, where the central electrode is coated with a thin layer of this metal. Do not use a knife, awl or screwdriver. They will cause deep scratches that will cause rust. Before starting the procedure, be sure to prepare all the necessary equipment:

• rust and plaque remover;
• small plastic dishes (it is advisable to use disposable ones, for example, cups):
• toothbrush or paint brush (hard bristles only);
• rags.

To completely clean black spark plugs, follow the steps below:

1. Pour cleaning solution into a plastic cup or similar container.
2. The liquid level should be leveled so that the electrodes of the spark plugs are completely immersed in the composition. The insulator does not submerge.
3. Leave the parts in the detergent for half an hour.
4. Take out the candles one by one. Use a brush to remove carbon deposits from the surface. Rinse off plaque in warm water.
5. Carefully remove all moisture using a prepared rag.
6. Final drying. Place candles on the radiator or use a hair dryer to remove moisture.

After this, they can be put back in their seats. As an alternative to detergent, drivers can prepare a 20% ammonium acetate solution. You can use a sink cleaner, citric acid solution or table vinegar. The use of Coca Cola and similar products is widespread. Such drinks effectively dissolve rust and carbon deposits. Remember that different compositions require different times (for example, parts should be left in acetone or vinegar for at least 1 hour). Specialized auto repair shops use an ultrasonic cleaning method. The candles are partially placed in a bath with a special solution. Afterwards they are exposed to ultrasound, which peels off any plaque. This is a professional cleaning that you will have to pay for, but it is extremely effective. If the cost of the procedure exceeds the price of suppositories, then it is rational to purchase a new set. It is worth considering that when cleaning, chemically active substances can enter the electrodes, damaging the protective layer. This can be eliminated in several ways: it is recommended to treat metal surfaces with WD-40 or cover them with plastic packaging. Now you know when and for what reasons black carbon deposits occur, as well as other types of carbon deposits. Methods of counteraction directly depend on the type of raid. Be sure to identify the cause and replace the spark plugs. If the parts are relatively new, perform a thorough cleaning using the above method. Remember that cleaned candles work on average 10-15 percent more efficiently.

Carburetor VAZ 2107, 2106, 2109, 2110

I would like to dwell in more detail on carburetor cars VAZ 2107, 2106, 2109, 2110, what you should pay attention to first if black spark plugs are found in them.

First of all, pay attention to the “behavior” of the engine, whether it revs or not. If the spark plug is black and dry, then the fault lies in the fuel system, and if it is wet, then in the oil that has penetrated into the combustion chamber. The problem may also be in the ignition, which is set incorrectly.

Pay attention to the carburetor, check:

1. The second chamber - it must be dry;
2. Is the mixture quality screw adjusted correctly?
3. How is the fuel level in the float chamber adjusted - if it is incorrect, then as a result of overflow the fuel mixture will become richer and as a result the spark plugs will turn black. The check should be carried out with the carburetor upside down and the top cover removed. The float is located 7-8 mm from the level of the gasket plane. On Solex you can do 10 mm.
4. Is the magnetic solenoid valve adjusted correctly?
5. How much fuel is in the float chamber? The norm is 2.5 cm from the top edge of the chamber (with the top cover removed) to the surface of the gasoline.
6. Check the auto choke. If it is present and faulty, then as a result of a closed damper, an enriched mixture is formed, as a result, the spark plugs are black.

You also need to check the condition of the spark plug itself, the high-pressure wire (may break through to ground), and the distributor. Don’t forget about the ignition coil, how to check it, read here https://autotopik.ru/sovet/997-kak-proverit-katushku-zazhiganiya-multimetrom.html.

If the engine does not start to stall immediately, but after warming up, then again go through the above points, plus, check the valve adjustment.