How to choose spark plugs correctly for VAZ cars?

How to choose the right spark plugs for a VAZ

When choosing the best spark plugs for a VAZ engine, you should be guided by the parameters of the car and engine:

1. Heat number. If a spark plug is approved for use on a specific car, then it will be suitable in terms of its thermal characteristics. Small deviations play a seasonal role and depend on the owner’s driving style.
2. Geometric dimensions - diameter and thread pitch, length of the threaded part of the body. Protrusion or recession of the electrode area into the material of the block head is not allowed.
3. The nominal gap between the electrodes can be adjusted. The spark plug will operate uninterruptedly at the factory-set value.
4. The wrench size is of secondary importance and affects the applicability of the existing tool. It is always safer to choose the size that matches the factory size.
5. The sticking out of the electrodes has an indirect effect; the heat rating depends on it.

You should not get carried away with high-reliability spark plugs that have two to four side electrodes instead of the standard one. This will do little, but massive protruding parts can shield the working gap from the mixture flows in the cylinder, which will worsen the conditions for uninterrupted ignition.

All kinds of “patented” products mentioning plasma ignition, annular gap or with miniature prechambers are mostly advertising gimmicks; they will not work normally in all modes. It is better for the engine not to mess with such devices.

With contact ignition

Contact battery ignition was used on outdated engines with a carburetor and 8 valves, for example, VAZ models 2106, 2107 and the like. Such products have a reduced spark gap, since the power of the simplest ignition system is small, the secondary voltage cannot reach this value. The situation is saved by the low compression ratio of older engines. The higher the pressure at the end of the compression stroke, the more difficult it is to break through the spark gap.

Small size and power do not seem to be an obstacle to the operation of the motor. The engines are not particularly economical or environmentally friendly; the carburetors prepare a fairly rich mixture, which is not difficult to ignite even with a weak spark.

With contactless ignition system

For the first time, the contactless system was used on models 2108, 2109, early 2110, then engines of the classic family with Solex carburetors capable of preparing a lean mixture were equipped with such devices. The distributor with a Hall sensor worked on an electronic switch, which developed significant power in the secondary circuit; the voltage was enough to break through the increased spark gap at high pressure. It was possible to install more modernized candles or increase the gap in the classic ones.

For injection engines

With the advent of electronic fuel injection systems, ignition power has increased even further. The distributor has failed. Ignition modules with several coils or blocks for each spark plug without high-voltage wires have appeared. Requirements for parts have changed, including radio interference suppression. Such devices are not interchangeable. The injector can prepare lean and ultra-lean mixtures, while the engine maintains uniform thrust, which a carburetor cannot do.

Injection engines were installed on VAZ models 2114, 2115, 21074, which have 8 valves, and 2112 - 16 valves. These are modern units for their era, so choosing candles for them will not be difficult - many imported analogues are suitable.

Design features of candles

VAZ 2114 spark plugs, as well as any other spark plugs, are a combination of the following structural elements:

1. Metal body. On one side there is a hexagonal protrusion that serves to tighten the spark plug with a wrench, and on the other side there is a thread cut necessary for screwing into the cylinder head. The housing absorbs more than half of the heat generated by the spark plug at the moment of firing, after which it transfers it to the cylinder head.
2. Insulator. Made of heat-resistant ceramics with the addition of aluminum oxide. Serves as a dielectric layer between the spark plug contacts.
3. Thermal cone skirt. Located at the bottom of the insulator. Receives and transfers 21% of the heat generated during candle operation.
4. The electrodes are central, located inside the spark plug head, and side, L-shaped and hanging over the central one. Serve for sparking.
5. Thrust washer and O-rings.

Spark Plug Design All components of a spark plug are extremely important for its operation, but special attention is paid to its electrodes. To increase service life in combination with better electrical conductivity and corrosion resistance, they are most often made from alloys with a high nickel content, and on high-end candles they are additionally coated with silver, palladium or gold.

Rating of the TOP 5 best spark plugs for VAZ cars

Copper-nickel spark plugs for VAZ cars of the “Standard” category are used on carburetor engines with a contact ignition system; their reliable service life does not exceed 10,000 kilometers.

Attention! These are products with a good reputation, so they are massively counterfeited. The rules for identifying the original can be found on the manufacturers’ websites.

NGK 7529 BP6E

NGK 7529 BP6E

The spark plugs are universal and work across the entire range of temperatures and loads. They are resistant to the formation of deposits on the insulator, maintain the shape of the electrodes and the size of the gap. V-line technology ensures uninterrupted sparking. The copper rod in the central electrode removes heat, preventing overheating and damage to the insulator. The sealing of the housing is adequately done, the tightness is always at its best.

The gap for these spark plugs is 0.9 mm. This means that it is better not to use the product for a carburetor engine, only an injector.

The price for such quality is attractive and does not go out of the general range in the category.

The cost of candles is, on average, 150 rubles per piece.

Advantages and disadvantages

Good engine starting in any weather.

Sparking without interruption due to the use of new technology.

Excellent tightness.

Compliance price/quality.

There are often fakes on the market

Basic tips for choosing spark plugs for VAZ

Representatives of the AvtoVAZ automaker advise choosing spark plugs taking into account the following features:

1. Heat number. The indicator indicates the intensity of thermal energy removal from the working part of the candle. The electrode sends excess heat to the part skirt in a timely manner, ensuring its proper functioning. When energy is transferred too quickly, scale appears on the surface of the spark plug, preventing spark breakdown. If the tap is weak, it causes the thin electrode to overheat. The phenomenon ensures the formation of glow ignition, which prevents the normal operation of the power plant due to the ignition of the air-fuel mixture before the required time. With balanced heat transfer, the spark plugs normally spark without creating carbon deposits.
2. Spark gap. For smooth operation of the engine, it is necessary to maintain the correct gap on the spark plugs - this parameter is determined by the manufacturers of VAZ engines. It is needed due to the presence of corresponding force in the electric arc. As the gap widens, the spark becomes unstable, causing misfires. If the distance narrows, the unit starts up faster, but when the gas pedal is pressed hard, a deficiency in the electric arc current occurs. Such phenomena are due to the fact that each ignition coil has a special transformation ratio, which, by default, is 2,000 units. This indicates that when the engine starts, the parts generate up to 14 kW, and during normal operation - already 24 kW. If the parameter is not observed, dangerous deviations in the functioning of the motor cannot be ruled out.
3. Departure of the main part of the electrodes. This property is an indispensable requirement for the correct operation of engines in VAZ cars. Spark plugs for models of the domestic automobile industry with 8-valve injectors and carburetors have electrodes slightly extended forward. This design is due to the following: the parts are located in the corner of the combustion chamber, where there is no normal air exchange. The presence of an overhang contributes to more efficient ignition of the mixture and improved engine performance. If the plugs are in a multi-valve engine where the inserts are located in the central part of the valve heads, it is better to choose plugs with deep seat cores. This modification will eliminate the problem of electrode failure when interacting with the piston bottom, as well as prevent the appearance of carbon deposits on important elements.
4. Number of electrodes. In the past, spark plug suppliers claimed that the more electrodes a part had, the better it was. If one element burns out, the spark plug automatically switches to another, serviceable one, which has a positive effect on its service life. But in practice, the situation looks different: if the fuel-air mixture is sprayed unevenly (due to poor air exchange in the combustion chamber), and the spark ends up in the exhaust accumulation zone, this can cause misfire and incorrect engine operation. This factor increases the likelihood of wear of the catalyst and engine oil, which can become a critical failure for AvtoVAZ cars.
5. Reputation of the manufacturing company. An important selection criterion is the rating of the company that supplies the product to the market. Experts recommend purchasing spark plugs from trusted suppliers. In this case, the components will work properly and for a long time without affecting the functionality of the power plant.

Using the tips listed above, you can choose a truly high-quality part, reducing the frequency of vehicle maintenance.

BOSCH W7DC

BOSCH W7DC

Such candles have a working range that provides versatility of use. Sometimes they work on motors that require different temperature characteristics, which emphasizes the stability of German products.

The model is well assembled - it consists of a copper core and a shell with increased anti-corrosion properties. The gap here is 0.7-0.8 mm. The key size is 20.8.

One can note some optimism in setting the heat number in relation to old VAZ car engines.

The average cost for one candle is 150 rubles.

Advantages and disadvantages

High-quality assembly of the part.

Uninterrupted operation under heavy loads and low temperatures.

Price corresponding to quality.

The mixture may get on the spark plugs.

Replacement process

Before replacing, you need to prepare: study safety precautions, select the necessary tools and materials.

Safety rules when replacing spark plugs:

1. Carry out the replacement procedure when the engine temperature drops below 30-40 degrees Celsius. Thanks to this recommendation, you can prevent the occurrence of burns on the skin.
2. Disconnect the on-board network. To do this, disconnect the negative terminal of the battery.
3. Wear gloves. They will help protect your hands from minor injuries.

Required tools and materials:

• Candle key;
• Compressed air cylinder;
• Brush for removing dirt;
• New ignition elements;
• Gloves.

Step by step procedure for replacing spark plugs:

1. Stop the operation of the power unit. Wait until it cools down to an acceptable operating temperature.
2. Lift the hood lid. Using a special design, fix it in the open position.
3. Grab the rubber caps of the high-voltage wires and carefully pull them out of their installation locations.
4. Clean the surface from dirt using a brush.
5. Unscrew the ignition element using the key.
6. Carry out similar actions with the remaining candles.
7. Check the new spark supply element. Measure the gap between the electrodes.
8. Tighten the consumable by hand. Complete an action using a tool.
9. Connect high voltage wires.

Please note: the main mistake of a novice car owner is to confuse the wires. You can't do this. High-voltage wiring is connected according to the markings in strict sequence for each cylinder.

After replacing the spark plugs, an unpleasant surprise may await the car owner. The engine speed may “float”, the engine jerks. Reason: perhaps a novice car owner purchased a low-quality ignition part. Defective goods must be returned.

It is easy to find out which ignition element is not working. To do this, the high-voltage wires are disconnected one by one. If the engine sound remains the same, the part is faulty and must be replaced.

DENSO 3043 W20EP-U

DENSO 3043 W20EP-U

The best candles for this application took first place in the ranking. Experienced car service workers always recommend Denso products, knowing that the client will be satisfied. There will be no complaints about the candles; the products guarantee their operation regardless of the mode - idle or load.

There are some downsides - the U-Groove technology does not prevent you from driving on a cold engine at low speeds, soot formation is possible, the spark plugs are a little colder in heat rating than inexperienced drivers would like.

The gap on the product is 0.8 mm, therefore, it is not suitable for a carburetor engine.

The cost, on average, is 130 rubles per unit.

Advantages and disadvantages

Excellent quality, which is why spark plugs are installed on many cars from the factory.

Copper core ensures reliability.

Increased flame spread thanks to the U-shaped groove of the side electrode.

Soot quickly forms on candles.

What are the types of defects and damage to spark plugs?

During operation, damage and defects may appear on the spark plugs. Sometimes they are the result of improper operation, sometimes due to the wrong brand of spark plugs. Defects on the spark plugs can also help diagnose engine problems. You will learn from this section of the article what will happen if you do not change the spark plugs if defects occur. The brown color of the electrodes and the absence of damage indicate that the spark plugs are operating normally, and you can continue to drive.

Examples of defects and description:

• The electrodes and housing are filled with oil. This defect indicates that the removable rings on the pistons are worn out and require replacement. It is the rings that allow oil to pass through, and the plugs filled with liquid spark irregularly and detonate. The engine needs to be repaired urgently. Dirty igniters must be washed from oil, dried and inspected. If there are no other defects, then they can be left for further use.
• The electrode insulation is broken . You cannot drive with chipped insulation; you need to change the spark plugs, as they cause detonation in the engine.
• Plaque on the surface of the body indicates low quality gasoline. It is necessary to change the gas station that sells the surrogate, and clean the spark plugs from deposits that prevent a spark from occurring, and you can continue to drive on them.
• Overheating of the housing is indicated by white spark plugs or a worn out upper electrode. Ignition devices can overheat for two reasons:

1. You use high-octane gasoline, which means you need to change its brand;
2. The type of spark plugs is not suitable for your engine and therefore they also need to be replaced.

• A lean mixture and the formation of carbon deposits inside the cylinders are indicated by the white color of the insulator with a smoky tint to the body and slightly melted electrodes.
• Painting the body and contact in a golden or glossy color, as well as mechanical damage, indicate that this brand of spark plugs is not suitable for your engine. The last defect occurs due to the excessive length of the element. Incorrectly selected, long specimens can damage the piston. Therefore, they also need to be replaced.

Degree of wear of spark plugs

A worn spark plug is perhaps the most correct type of malfunction. It says that the ignition process was carried out correctly, the internal combustion engine is working normally, but the time has come to replace them with new ones.