How to judge the quality of a spark plug and what are the ways to distinguish the quality of a spark

Hello subject, the engine has just started, you can directly touch the spark plug shell with your hand to compare its temperature to diagnose, the higher temperature works normally, otherwise there is a fault. The temperature of the porcelain surface of the hot engine is very high, do not touch it with your hands, you can keep the engine running at idle speed, touch the high-pressure divider of each cylinder with your thumb and index finger in turn for a few seconds, and judge which cylinder's spark plug is faulty according to the feel. The normal working high-voltage distribution line is obviously pulsating when touched by hand, and the faulty high-voltage distribution line feels that the pulsation is not obvious, no pulsation, or the pulsation is intermittent.

After determining that a cylinder is working poorly, it should be further checked, and if there is no other reason, the spark plug is faulty. Idle the engine, use a screwdriver to deactivate the spark plug (tie iron), if the spark plug is faulty, the engine operation will remain unchanged (the engine itself needs to be ruled out). If the engine shakes immediately after the fire is broken, it means that the cylinder is working properly.

Remove the suspected faulty spark plug and place it flat on the engine block, unplug one end of the high-voltage bus distributor and make contact with the spark plug terminal. Turn on the ignition switch and toggle the distributor platinum. Make the high-voltage electricity jump between the spark plug electrodes, if the spark is continuous and bright, the spark plug is good, otherwise the spark plug should be replaced. Thank you!

During use, the spark plug should have the following characteristics: the surface of the porcelain core should be clean, white or light brown, or the porcelain core should have a very thin layer of brown powdery carbon; The electrode must be intact and gray, with no ablation on the surface; The front end of the thread body is dry, and the surface is brown or maroon-red.

The spark plug needs to be replaced if:

1. The head electrode or side electrode of the spark plug has obvious wear and consumption, and it is recommended to replace it, which is easy to cause ignition instability and increased fuel consumption.

2. Too much carbon deposition or reddish in the ceramic of the spark plug head, indicating that the quality of gasoline is not very good or there are inferior additives, which will one-sidedly affect the heat dissipation of the spark plug, so try to replace it in advance.

According to Bian Xiao's understanding, many friends don't know much about Brother La's late car knowledge. In order to make it easier for everyone to understand these knowledge, today Bian Xiao will introduce you to some methods about distinguishing the good and bad spark plugs. Interested friends can learn about this problem, which may be helpful to you.

1) Ignition: Screw the flower plug, put it on the cylinder block, and test the ignition with a high-voltage line. If there is no spark or the spark is weak, the spark plug is leaking or not working.

2) Short circuit: Let the engine idle and use a screwdriver to short-circuit the spark plug cylinder by cylinder, and listen carefully to the engine speed change and noise. The speed and noise changes are clear, indicating that the spark plug is normal. Moreover, the speed and noise are basically unclear, indicating that the spark plug is in an abnormal state.

Observe the appearance color: Friends can learn this method, and the wheel repairman can judge and test by himself after removing the spark plug. Remove the spark plug and observe it, and judge the use of the spark plug according to the following appearance color observations:

1) If the spark plug is seriously ablated, there are scars, black lines, cracks and electrodes melted on the top, it means that the spark plug has been damaged and must be replaced immediately;

2) If it is smoky black, it means that the spark plug is not hot and cold or the mixture is thick, and the engine oil is running out;

3) If there is a deposit between the top and the electrode, the deposit is an oily dust calendar, indicating that the oil has escaped from the cylinder and has nothing to do with the spark plug; If the sediment is black, the spark plug is bypassed; The gray deposits are due to a lack of fire caused by additives in the gasoline that covers the electrodes;

4) If it is russet or rust colored, it means that the spark plug is normal;

5) If it is oil quality, it means that the spark plug gap is unbalanced or the oil supply is excessive, and the high-voltage line is short-circuited or open-circuited.

The quality of the spark plug determines the following three ignition situations:

1. Ignition of the morning and evening. 2. The order of ignition. 3 Intensity of ignition.

How to tell if a spark plug is good or bad

1) Flashover: unscrew the spark plug, put it on the cylinder block, and test the fire with a high-voltage wire, if there is no spark or the spark is weak, it indicates that the spark plug is leaking or not working.

2) Short circuit: Let the engine idle and use a screwdriver to short circuit the spark plug cylinder by cylinder, listen carefully to the changes in engine speed and sound, the speed and sound changes are obvious, indicating that the spark plug is normal. When the speed and sound are not obvious, it means that the spark plug is in a state of abnormality.

2. Observe the appearance color: the owner can learn this method, and after the maintenance personnel disassemble the spark plug, they can judge and check the spark plug.

Remove the spark plug and observe it, and judge the use of the spark plug according to the following appearance color observations:

1) If the spark plug is severely ablated, and the top is scarred, black, cracked, and the electrode is melted, it indicates that the spark plug has been damaged and must be replaced immediately;

2) If it is smoked black, it means that the spark plug is selected incorrectly or the mixture is thick, and the oil is on the way;

3) If there is a deposit between the top and the electrode, and the deposit is oily, it proves that the cylinder channel oil has nothing to do with the spark plug; If the sediment is black, it means that the spark plug has deposited carbon and bypassed; The gray color of the sediment is due to the lack of fire caused by the additives in the gasoline covering the electrodes;

4) If it is russet or rusty, it means that the spark plug is normal;

5) If it is oil-stained, it indicates that the spark plug dust spike gap is out of balance or excessive oil supply, and the high-voltage line is short-circuited or broken;

Judging the quality of the spark plug: the key is whether the gas turbine has an effect. It can be tested with a universal meter, and the color of the spark plug can be seen in the bad draft, the gray-yellow color is normal, the black burns badly, and the carbon deposits burn a lot of oil.

The intermediate electrode is corroded and needs to be replaced. After disassembly, install the cylinder line, let the side of the spark plug touch the iron, and observe whether the ignition is strong or weak, and whether the heart is beating inside the spark plug. Weak sparks or ignitions around the spark plug electrodes also need to be replaced.

Judge the quality of the spark plug as follows:

1) Flashover: Screw the flower plug, put it on the cylinder block, and test the fire with a high-voltage wire. If there is no spark or a weak spark, it is an indication that the spark plug is leaking or not working.

2) Short circuit: Let the engine idle and run it, use a screwdriver to short-circuit the spark plug of the cylinder one by one, and listen carefully to the changes in engine speed and noise, indicating that the spark plug is normal. When the speed and noise are not obvious, it indicates that the spark plug is in an abnormal state.

2.Observe the appearance color: After disassembling the spark plug, the maintenance personnel can judge and inspect it by themselves.

Remove the spark plug and observe it, and judge the use of the spark plug according to the following appearance and color observations:

1) If the spark plug is severely ablated, there will be scratches, black lines, cracks and electrode melting on the top, which means that the spark plug has been damaged and must be replaced immediately;

2) If it is blackened, it means that the hot and cold spark plugs are not right or the mixture is too thick, and the oil is running;

3) If there is a deposit between the top and the electrode, and the deposit is oily, it proves that the oil leakage in the cylinder has nothing to do with the spark plug; If the sediment is black, it means that the spark plug deposits carbon and bypasses; The gray deposits are caused by the lack of fire caused by the gasoline additives that cover the electrodes.

4) If it is russet or rusty, it means that the fire makes the filial piety plug normal;

5) If it is oily, it means that the spark plug gap is unbalanced or the oil supply is excessive, and the high-voltage line is short-circuited or open-circuited;

See if there is any impact when the gas turbine is critical. You can use a multimeter to test the color of the spark plug, the gray-yellow color is normal, the black burns badly, and the carbon deposits burn a lot of oil. The middle electrode is corroded and needs to be replaced.

After disassembly, install the cylinder line, let the side of the spark plug touch the soldering iron, and observe the ignition strength and whether the heart is beating in the spark plug. Weak sparks or ignition around the spark plug electrode.

See if there is any impact when the gas turbine is critical. You can use a multimeter to test the color of the spark plug, the gray-yellow color is normal, the black burns badly, and the carbon deposits burn a lot of oil. The middle electrode is corroded and needs to be replaced.

After disassembly, install the cylinder line, let the side of the spark plug touch the soldering iron, and observe the strength of the ignition and whether the heart is beating in the spark plug. The faint spark or ignition around the spark plug electrode also needs to be replaced.

Ignition: Screw the ** flower plug, put it on the cylinder block, and test the ignition with a high-voltage line. If there is no spark or the spark is weak, the spark plug is leaking or not working.

Short circuit: Let the engine idle and use a screwdriver to short circuit the spark plug cylinder by cylinder, listen carefully to the engine speed change and noise, indicating that the spark plug is normal. When the speed and noise are not obvious, it means that the spark plug is in an abnormal state.

The spark plug can be removed and the color of the electrode can be observed, which is normally off-white. See if the electrode core is ablated and whether the gap is too large. If there is too much carbon on the surface, it means that the combustion is insufficient or the oil has burned out. It needs to be replaced.

How to divide the spark plug.

Spark plug specifications: The main thread diameters abroad are M14 and M12, followed by M10 M14 in China, and M12 and M10 spark plugs are produced under special circumstances. The mountain fissure cavity representation method of spark plug models in different countries is different, such as T8126J spark plug, where "T" represents the structure type, "8" represents the thread size and hexagonal opposite edge, "12" represents the thread screw-in length, "6" represents the heat generation, and "J" represents the characteristics.

Common types of structures are standard (denoted by b) and convex (denoted by t). There are three thread sizes, where 1 means M10, 1, S = 16 means M14, S = 198 means M18, and S = 22. There are three thread tightening lengths and 19.

Includes nine calorific value numbers from 1 to 9; Among them, 1 3 is a low calorific value, 4 6 is a medium calorific value, and 7 9 is a high calorific value. The higher the heat generation, the faster the heat dissipation, which is a cold spark plug; The lower the heat generation, the slower the heat dissipation. It's a spark plug.

The selection of spark plug model should be based on the specifications specified by the original factory.

How to see good and bad spark plugs @2019

<> "How to look good or bad with spark plugs?

In the maintenance process of the car, the spark plug is an indispensable and important part, its role is to make the engine can start normally. If the spark plug does not start properly, then the engine will not work. Therefore, the quality of the spark plug directly affects the power of the car.

So, how can you tell if a spark plug is good or bad?

Look at the color. The color of the spark plug is also an important factor in differentiating good from bad. During the use of spark plugs, due to the influence of oil and burning moisture in the air, a layer of sludge will be formed on the surface of the electrode and insulator, and carbon deposits will be formed if not removed in time.

Excessive carbon deposition will lead to leakage at the end of the spark plug insulator and the central electrode, which will affect the engine power and torque, and make the engine difficult to start, poor acceleration, unstable idling, and weak driving. If too much carbon is deposited in the spark plug, it will produce an abnormal sound.

The normal spark plug should be black or silver-gray, if there is a white or red phenomenon, it means that the spark plug has been heavily deposited. In this case, the spark plug needs to be replaced in time. If it is not replaced in time, it will also affect the normal operation of the engine.

Look at the thickness. Generally, the ratio of the outer diameter size to the diameter of the spark plug, such as the outer diameter of the No. 1 spark plug is 5 mm, the diameter is 7 mm, and the gap should be within mm; For example, the outer diameter of the No. 1 spark plug is 7 mm and the diameter is 8 mm, and the gap should be between mm in order to make the high voltage work normally.

Look at the gaps. The electrode gap of a normal spark plug should be between mm, and the size of the gap should be uniform. If it is found that there is a gap in the spark plug, then it proves that there is a problem with the electrode of the spark plug, if the gap is too large, then the engine cannot start normally; If the clearance is too small, the engine will also have symptoms such as unstable idle speed and poor acceleration.

Look at the ignition ability.

The spark plug plays a vital role in the working of the engine, it will ignite the high voltage electricity generated by the spark plug, forming a spark to ignite the mixture. Therefore, if the performance of the spark plug is poor, ignition will be difficult, resulting in a drop in engine power and even a malfunction of the car.

Generally speaking, the deterioration of spark plug performance is mainly manifested in the decrease of power, the increase of fuel consumption in the dust section, and the unstable idle speed. In order to ensure that the car can start, accelerate and drive normally, the car user must replace the spark plug regularly. Therefore, when replacing the spark plug, it is necessary to pay attention to the choice of the most advanced and stable spark plug brand to ensure engine power and driving safety.

A good spark plug can not only bring better power performance to the vehicle, but also prolong the engine life, so when choosing a spark plug, you must choose the best and stable performance.