The frequency of replacing spark plugs depends primarily on their type, or more precisely, on the material of the central electrode, as well as vehicle operating conditions, fuel quality, timeliness of oil changes, interruptions in engine operation and other external factors. According to the regulations, the service life of nickel spark plugs is 45,000 km, platinum – 80,000 km, iridium – 120,000 km. In practice, they fail 1.5–2 times faster. The average interval for replacing spark plugs is 30-60 thousand km .
Read our article about how often you need to change spark plugs, what signs indicate the need for immediate replacement, and what can happen if you don’t replace the spark plugs in time.
Change intervals for ignition system components
Every car model has a manual. So, it is in this “smart” book that the period for replacing consumable parts and fluids is carefully described.
If you follow these recommendations, you will not have any major repairs to your vehicle for many years.
Averaged indicators for different brands of cars can be indicated as:
- Simple spark plugs are changed every 25,000 kilometers.
- Spark plugs with platinum and iridium are changed every 100,000 km.
When the machine is operated only for short distances, carbon deposits may form on the spark plugs prematurely. The reason is that the engine does not have time to warm up properly. It is recommended to thoroughly warm up the engine at idle speed at least once every 7 days.
Modernization, its impact on service life
Three-electrode spark plug.
The main structural components of the spark plug are two electrodes and an insulator. The service life of the product is affected by the burnout rate of the contacts; the higher it is, the shorter the operational period of the SZ. In this case, the contact area should not be overestimated, otherwise the spark will be of low power. The power of the spark affects the rate of fuel combustion; it is important that the fuel burns completely without residue, this ensures long-term and stable operation of the engine and its high efficiency. Thus, special requirements are imposed on the materials from which spark plug contacts are made. To ensure a long service life of spark plugs, manufacturers increase the number of electrodes, but the contact area does not increase.
To improve spark plug electrodes, soldering from the following materials is used: platinum or iridium. They provide greater spark power in harsh operating conditions, make it possible to reduce the central contact during product manufacture - this helps reduce voltage, reduces the load on the coil, and improves combustion of the combustible mixture. The service life of such products is 60 thousand km. The company's iridium products, for example, NGK, have a high melting point and a very low probability of erosion (contact burnout). At the same time, the contact cross-section is very small, up to 0.5 mm. Plus, an additional recess between the insulator and the electrode allows for a high degree of self-cleaning of the spark plug from deposits.
Prechamber SZ have a design feature: the body of the product is a lateral contact. Such spark plugs have an improved degree of self-cleaning and an increased service life of up to 60 thousand km.
Advice for car owners
- If, after changing the spark plugs, little time has passed before the malfunction appears, then it is allowed to change only the damaged spark plug. But when a set of spark plugs has been used for a long time, then if it breaks, it is better to change everything.
- The section on candles must be carefully studied in the manual.
- If during checking the spark plugs it was discovered that they are like new and there are no interruptions in the operation of the car, then it is not forbidden to leave them for another couple of tens of thousands of kilometers.
Recommendations from the experts
- Even if there are indirect signs of faulty spark plugs, it is worth taking the car to a dealership or checking the spark plugs yourself, if possible. If it turns out that only one spark plug is faulty, the entire set will have to be replaced.
- If you still decide to find the reason yourself, then adhere to some rules: - all manipulations can be carried out only on a cooled engine, otherwise you can break off part of the spark plug so that it remains inside the engine; - work only with a special spark plug wrench, which has a special working area; - dismantle spark plugs only in a room free from wind, snow and other weather conditions to avoid debris getting into the cylinders; - use a compressor.
- Read the instruction manual carefully, it clearly states what kind, how many and for how long spark plugs are needed.
Replacement process
Tools and materials:
- Special key for candles;
- Compressor.
Progress:
- Unscrew and put aside all unnecessary elements.
- Disconnect the high-voltage wires, hold only the tip.
- Blow out the spark plug well using a compressor.
- Use a spark plug wrench to unscrew the old system element.
- Assess the condition of the parts.
- Whether an old or a new spark plug, when screwing it into place, press it with your hand so that the thread falls into place.
- Replace the high voltage wire.
- So check all the spark plugs.
- After checking and replacing, screw back all previously removed parts.
In almost all cars, spark plugs are changed in the same way. The only difference is the number of parts that need to be removed.
This is necessary and important to know
Due to their design features, the spark plugs are located inside the engine, and therefore their level of wear cannot be determined without removal. When replacing them, you must remember to install all products at the same time.
Another condition is that the products must be from the same manufacturer. When purchasing them, you should give preference to well-known brands and brands. Some of the best companies are in Germany and Japan.
You can determine how often you need to change spark plugs by looking at the ceramic insulator; it may have chips and cracks, and there may be a brown coating inside that will interfere with the proper functioning of the unit. Carbon deposits occur when using low-quality fuel. In this case, it is better to immediately replace the old products with new ones.
Advice! To check the condition of the devices, they must be unscrewed from the socket. This operation is performed using a special key with the cooled engine not running. If the spark plug is faulty, it is very easy to determine visually. Soot is visible on it, the spark plug is wet and yellow spots are visible on the electrodes.
Before replacing products, the hole into which the spark plug is inserted should be cleaned of contamination. This is done to prevent foreign particles of debris from entering the engine cylinder.
After this, the device is inserted into the seat and tightened. This must be done carefully, since with too much force you can damage both the thread and the candle jacket itself.
Currently, manufacturers produce several types of candles, which can be divided into two groups:
Multi-electrode spark plugs
Multi-electrode ones have a longer service life than two-electrode ones; they allow the ignition system to function for a long time and reliably, up to 50 thousand kilometers. But two-electrode ones are not so reliable - if the working electrode fails, the product immediately becomes unusable.
Attention! Before replacing spark plugs, you should carefully study the requirements set by the car company, according to the instrument operating book. Be careful when working with car devices yourself!
Is it possible to keep the old spark plugs?
But what happens if the candles are not touched for a long time? There are several options for the outcome of the situation.
- The most common outcome is the inability to start the car. And most often this happens at the most inopportune moment. And before that, there may not even be other signs of a malfunction in the vehicle.
- Another outcome is friction in the engine at idle. This means that the gap between the electrodes has increased and unburned fuel mixture passes into the system. This can cause the coils to break, which will result in a much higher repair cost for the car owner.
- When fuel injection malfunctions or the gaskets in the system are worn out, the spark plugs will quickly become oily, which will lead to car breakdown.
- There are also cases when the spark gap is smaller or larger than required, and it is impossible to buy another spark plug. Then use available tools to correct the gap. This is enough to get to a car repair shop or a spare parts store and buy a new set of spark plugs.
A spark plug is a guarantee of efficient engine operation.
Such a small engine part can negatively affect the operation of the entire power plant. Thanks to them, the fuel mixture ignites in the engine cylinders. Ignition occurs from a spark that is generated at the electrodes of the spark plug. A high voltage is applied to the electrodes and a breakdown of the gap between the electrodes occurs. The presence of carbon deposits on the products impairs the operation of the mechanism, causing the engine to lose power and operate unstably.
When to change spark plugs? And why?
For proper operation of the vehicle's power plant, it is necessary to change these products at certain intervals. The level of their work is influenced by the following factors:
- low-quality gasoline;
- poor engine condition.
Due to these negative factors, carbon deposits form on the devices and, as a result, ignition of the fuel mixture becomes difficult. Moreover, due to dirt, the ceramic jacket can be damaged and the unit may completely collapse.
Carbon deposits on spark plugs
Since low-quality fuel is common in our country, the service life of spark plugs is reduced several times; the unit replacement procedure must be carried out every 20-30 thousand kilometers. Of course, many motorists can boast of more impressive periods, for example, 50-100 thousand mileage, but such “sacrifices” are not at all necessary for the car.
Yes, but what will happen if you don’t change the spark plugs? Multiple problems will arise in the operation of the entire mechanism:
- the car will begin to twitch while driving;
- engine dynamics will decrease several times;
- fuel consumption will increase;
- You can damage various engine systems and disable the entire mechanism.
Important! In order to understand when you need to change your spark plugs, you need to check them periodically. Yes, sometimes it is not so easy, but if you have a simple four-cylinder engine, the spark plugs can be removed very simply. A visual inspection can determine the degree of contamination and take preventive measures to eliminate debris and soot.
Companies that produce these products recommend replacing them every 15,000 km. But with good fuel and proper operation of the power plant, the spark plugs can last longer.
Reasons for rapid deterioration of candles
There are several reasons why spark plugs become unsuitable for use ahead of time:
- Due to unsuitable fuel, carbon may form on the spark plugs or detonation may occur, damaging nearby components.
- Plugs with improper compression can increase or, conversely, decrease the temperature during fuel combustion, which will lead to failure.
- If the ignition angle shifts, the end of the spark plug overheats.
- In the cold season, the saturation of the mixture for combustion decreases.
- At high humidity, the temperature conversion of candles decreases.
If you have to frequently replace a set of spark plugs, you should conduct a thorough engine diagnostics. Naturally, it is impossible to correct natural factors, but everyone can supply high-quality consumables.
Let's sum it up
You need to change spark plugs according to the instructions of the company that released your car. This frequency must be adhered to, but no one is immune from force majeure circumstances. For example, if the fuel supply system becomes clogged, the spark plugs begin to work in the wrong conditions, so their service life is significantly reduced.
Also, if chips and cracks of the insulator are visible on the spark plugs, then under no circumstances should they be inserted back. A clear sign of replacement is also considered to be melting of the electrodes and large carbon deposits.
Better keep an eye on all the components of the car, in this case there will be no problems in the operation of the internal combustion engine and the spark plugs will be able to last for a very long time. In conclusion, I would like to say that you should not save money on servicing your car. Let's say you save on fuel, but in a few years this may result in a major overhaul of the engine.
Now you know everything about replacing spark plugs, how to do it correctly, and what you should pay attention to. All you have to do is go to the store and start replacing, we wish you success!
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What do the different shades on spark plugs mean?
When the spark plugs are in good condition, their electrodes are gray or brown. If the electrodes have a different color, this indicates a malfunction.
What does each of the shades mean?
- A small black soot indicates insufficient oxygen. You should check one of the elements: filter, throttle valve or ECU.
- Dense black carbon deposits from pouring oil into the candles. The operation of the engine should be carefully checked.
- A gray-white coating indicates a lack of gasoline in the combustible mixture. The fuel system should be completely checked.
- A red coating indicates bad gasoline. You should find a gas station with better quality fuel.
When to replace
Recognizing wear or malfunction of spark plugs is quite simple; you need to carefully observe your car and notice signs such as:
- Fuel consumption has increased several times over the last week and month, but the car itself shows no signs of breakdowns;
- The car does not start after the first attempt, you have to try hard to get it to go;
- And if problems arise when gaining speed.
The catch may be the fact that such “symptoms” may indicate malfunctions of the spark plugs and other systems of the car - the gas pump, fuel supply, air filter or even the exhaust system.
Important points
- Since spark plugs are installed directly into the engine, their inspection can only be carried out by disassembling some of the parts.
- Remember that whether to change all the spark plugs or just one depends on when the kit was installed.
- When unscrewing the spark plugs, you should use a special tool - a spark plug wrench.
- The spark plugs can only be removed from a cooled engine.
- Before replacing consumables, read the vehicle manual for specific instructions on removing parts.
- Before purchasing, check to see if the bushings are interchangeable for your car.
The importance of correct spark plug installation
The consumable element in question is often rendered unusable by its incorrect installation. The tightening torque of the candles plays a big role here. For each of them, the required moment is indicated on the packaging, but not everyone pays attention to it, and if they do, they consider this parameter to be of little significance. Therefore, not all motorists have a torque wrench - you can tighten it by hand to a certain angle. Practice shows that the torque with seemingly the same tightening force can differ by tens of N*m.
A smaller torque cannot provide the required level of tightness and fastening reliability. High, on the contrary, leads to disruption of the thermal characteristics of the candle and damage to the threaded part. Recommendations for tightening the spark plugs to a certain angle largely only prevent their incorrect operation, but this method is by no means correct, so it is important not only to know at what mileage to change the spark plugs, but also to install them correctly.
How to increase the life of spark plugs
There are several tips for extending the life of spark plugs:
- Train yourself to check the oil level.
- Use only suitable candles.
- Refuel only with high-quality fuel, do not skimp.
- Between recommended replacements, it is worth checking the spark plugs and, if possible, cleaning them from dirt and carbon deposits. Even if they still have to be changed, this will protect you from serious engine damage.
The most important thing is to regularly inspect the engine compartment of the car. If this rule is followed and careful care is taken, the car will work like a clock for many years.
Remember, it is best to stick to the manufacturer's recommended spark plug replacement schedule. If an emergency replacement is required, then naturally you should not wait for the scheduled time.
Check the heart of your car and its components on a regular basis. At the slightest sign of a part malfunction, it is better to replace it.
Your car, like a metal body, will give a signal about its poor condition, you just need to notice it in time. If you are not good at repairing cars yourself, then contact a trusted car service center. Regular minor fixes are better than major engine overhauls every couple of years.
Knowing all the subtleties of how a car behaves with faulty spark plugs, you will no longer wonder if it’s time to change them. And may your iron horse serve for a long time without failure.
General information
Motorists are not always able to purchase exactly the spark plugs recommended by the manufacturer. As a result, many candles stop working much earlier than expected, and this is fraught with serious consequences.
Spark plug
If one spark plug breaks, this can already provoke engine detonation. If it does not cause the death of the engine, then the spark plug must be replaced, and it is also advisable to carry out a full diagnostic of the engine.
