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How to judge engine carbon deposit?

How to judge whether there is carbon deposit in the engine

There must be carbon deposits in the engine cylinder. If it is very small, it will basically not affect the performance of the engine. The more carbon deposits, the greater the impact. If there is too much carbon deposit, the phenomenon may be that the engine idling is unstable and the engine is shaking greatly when you drive. In severe cases, it will make a "rattle" knocking sound. Excessive carbon deposition will also lead to engine cylinder fire, which will lead to engine fault light. It's time to go to the repair shop to clean up the carbon deposit. Your car has only driven so many miles in four years. There must not be much carbon in it. I suggest you let your car run on the expressway (300-500 km), clean up the carbon deposit inside, and then do maintenance after running. This is much better than idling in the garage all the time, and if the gasoline in your garage is not changed all the time, it is easy to produce sediment. I think I have too much to tell you, because I am an auto worker, and it is not enough to explain everything in three sentences. I hope you can continue to ask questions and I will try my best to answer your questions!

How to judge whether there is carbon deposit in the car?

If you encounter the phenomenon of slow speed increase, quick refueling and tempering, and difficulty in cold starting, then the valve of your car is likely to have carbon deposition. It is found that the idle speed is low, the card is issued by stepping on the accelerator, and there is no idle speed after changing the battery, so the carbon deposition in the intake pipe of your car is very serious.

How to judge whether there is carbon deposition?

In order to avoid the loss caused by uncovering the cylinder head, it is found that it is a gradual process from the formation and accumulation of carbon deposits to the normal operation of the engine. When the cold car engine is difficult to start and the idle speed is unstable, it shows that the carbon deposition is quite serious, which will further cause fire and cylinder failure until it cannot be started. When it is difficult to start the cold car, you should go to the repair shop for inspection immediately. After excluding other factors, the carbon deposit in the valve should be cleaned in time to avoid the loss caused by uncovering the cylinder head.

Carbon deposition in valves and combustion chambers

Due to the control characteristics of EFI engine, the cylinder is injected with oil first and then ignited every time it works. When we put out the engine, the ignition device was cut off immediately. However, the gasoline sprayed by this working cycle cannot be recovered and can only be attached to the intake valve and the combustion chamber wall. Gasoline is volatile, but wax and gum remain in gasoline. In the long run, the wax and gum in gasoline accumulate thicker and thicker, and harden after repeated heating, forming carbon deposits. If the engine burns engine oil, or the quality of gasoline is poor and there are many impurities, then the valve carbon deposition is more serious and forms faster. Because the structure of carbon deposit is similar to sponge, when the valve forms carbon deposit, a part of the fuel injected into the cylinder will be adsorbed every time, which will dilute the concentration of the mixture that really enters the cylinder, resulting in poor engine operation, difficult starting, unstable idle speed, poor acceleration, sudden refueling and tempering, excessive displacement and increased fuel consumption. In severe cases, the valve will not be closed tightly, so that a cylinder can not work completely because there is no cylinder pressure, and even the valve can not go back. At this time, the valve and piston will interfere with each other and eventually damage the engine.

Carbon deposition in intake pipe

Due to the unsynchronized operation of the pistons in the whole engine, when the engine is turned off, the intake valves of some cylinders cannot be completely closed, and some unburned fuel is continuously evaporated and oxidized, which will produce some soft black carbon deposits in the intake pipe, especially behind the throttle. On the one hand, these carbon deposits will make the pipe wall of the intake pipe rough, and the intake will produce eddy currents in these rough places, which will affect the intake effect and the quality of the mixture.

On the other hand, these carbon deposits will also block the idle passage, making the idle control device stuck or out of its adjustment range, resulting in low idle speed, idle jitter, failure of various auxiliary devices to increase speed, flameout of oil collection, excessive exhaust gas and excessive oil consumption.

If you encounter the phenomenon of slow speed increase, quick refueling and tempering, and difficulty in cold starting, then the valve of your car is likely to have carbon deposition. It is found that there is no idle speed when the idle speed is low, the card is issued by stepping on the accelerator, and the battery is changed, so the carbon deposition in the intake pipe of your car is very serious. With the above phenomenon, you should go to a professional repair shop to check the car in time.

It is very simple to diagnose carbon deposit in intake pipe in automobile maintenance. As long as the throttle is removed, the degree of carbon deposition can be clearly seen. However, the diagnosis of valve carbon deposit has always been a difficult problem. Generally speaking, there are three diagnostic methods in professional repair shops.

How to recognize engine carbon deposit?

There are many manifestations of engine carbon deposition, such as unstable idle speed, engine jitter and feeling that power is relatively insufficient. Cold start, no fire. Fuel consumption will also increase. I suggest you go to a professional repair shop for a test. When the engine deposits carbon, the cylinder pressure will also decrease.

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How to judge whether there is carbon deposition?

Hello, this is a simple way to get carbon deposit. If there is carbon deposit in the car, there will be problems such as difficult cold start, slow acceleration, idling trembling, quick tempering after refueling, stuck accelerator and excessive exhaust gas. But if these problems appear in the car, it means that the carbon deposition on the car is already very serious. Therefore, conventional vehicles must be cleaned once every six months or ten thousand kilometers. Because once carbon deposit is produced, the consequences are quite serious: 1 There is carbon deposit on the fuel nozzle of the engine, which leads to poor gasoline atomization and poor oil supply; 2. The larger the valve clearance, the larger the engine noise imprint; Because carbon deposit is like a sponge, it has the characteristics of absorbing gasoline, which invisibly increases fuel consumption, so that there is too much carbon deposit, the valve can't even be closed, and finally the alarm can't be started. Carbon deposition on piston will increase the wear of cylinder wall and fuel consumption, thus affecting the normal power of engine and shortening the service life of engine. Although your car has only driven 7000KM, that is to say, it belongs to a new car, but the inside of the engine of the new car is stuffy, which will wear out a lot of metal powder, which will produce gum and carbon deposit when attached to the engine. Therefore, in order to better maintain the engine in advance, the new car should be properly added with engine protective agent. By the way, some people will say that the new car can pull out the carbon deposits on the high speed. Yes, metal powder and colloid can be pulled out at high speed after the new car is 5000KM, but in this case, only about 3% clothes can be washed clean. I hope my answer is helpful to you.

How to judge whether there is carbon deposit in the car?

We often hear people complain about poor fuel quality, but people often ignore another culprit: crankcase ventilation. In order to prevent air pollution, engineers directly introduce the exhaust gas inside the engine into the intake manifold and enter the combustion chamber with fresh air for combustion. The high-temperature oil vapor fills the intake manifold with fresh air, one part of which adheres to the pipe wall and the back of the valve, and the other part is mixed with the injected fuel at the intake valve to form mixed vapor, which enters the combustion chamber and is discharged from the vehicle after combustion.

Because the inhaled air contains fine dust, it can't be completely filtered out in the air filter, and it washes the back of the valve together with oil and gas. After a long time, it will produce fine scratches. Particles and lubricating oil in the crankcase are stored in scratches, which will form paint at high temperature. After a long period of accumulation, they are mixed with wax and other components in fuel to form carbon deposits.

The direct consequences of carbon deposition on the back of the valve are poor acceleration of the engine, unstable idle speed, sometimes accompanied by slap of the intake manifold, difficult cold start and a series of other problems.

In order to avoid the loss caused by uncovering the cylinder head, it is found that it is a gradual process from the formation and accumulation of carbon deposits to the normal operation of the engine. When the cold car engine is difficult to start and the idle speed is unstable, it shows that the carbon deposition is quite serious, which will further cause fire and cylinder failure until it cannot be started. When it is difficult to start the cold car, you should go to the repair shop for inspection immediately. After excluding other factors, the carbon deposit in the valve should be cleaned in time to avoid the loss caused by uncovering the cylinder head.

Prevention and removal of carbon deposit

In view of the harm of carbon deposition, drivers should do the following work: firstly, they should maintain regularly to keep oil and gas clean; Secondly, carbon deposits should be cleaned every 20,000 kilometers (without disassembly and cleaning); Finally, pay attention to driving habits, avoid idling for a long time, avoid turning off the engine immediately after driving at high speed, and avoid driving at high speed immediately after starting, and control the shift timing at around 2000-3000 rpm.

After carbon deposition, the method of disassembly-free cleaning is usually adopted, and when it is serious, the method of uncovering the cylinder head to clean the valve is adopted.

How to judge whether there is carbon deposit in the car?

We often hear people complain about poor fuel quality, but people often ignore another culprit: crankcase ventilation. In order to prevent air pollution, engineers directly introduce the exhaust gas inside the engine into the intake manifold and enter the combustion chamber with fresh air for combustion. The high-temperature oil vapor fills the intake manifold with fresh air, one part of which adheres to the pipe wall and the back of the valve, and the other part is mixed with the injected fuel at the intake valve to form mixed vapor, which enters the combustion chamber and is discharged from the vehicle after combustion.

Because the inhaled air contains fine dust, it can't be completely filtered out in the air filter, and it washes the back of the valve together with oil and gas. After a long time, it will produce fine scratches. Particles and lubricating oil in the crankcase are stored in scratches, which will form paint at high temperature. After a long period of accumulation, they are mixed with wax and other components in fuel to form carbon deposits.

The direct consequences of carbon deposition on the back of the valve are poor acceleration of the engine, unstable idle speed, sometimes accompanied by slap of the intake manifold, difficult cold start and a series of other problems.

In order to avoid the loss caused by uncovering the cylinder head, it is found that it is a gradual process from the formation and accumulation of carbon deposits to the normal operation of the engine. When the cold car engine is difficult to start and the idle speed is unstable, it shows that the carbon deposition is quite serious, which will further cause fire and cylinder failure until it cannot be started. When it is difficult to start the cold car, you should go to the repair shop for inspection immediately. After excluding other factors, the carbon deposit in the valve should be cleaned in time to avoid the loss caused by uncovering the cylinder head.

Prevention and removal of carbon deposit

In view of the harm of carbon deposition, drivers should do the following work: firstly, they should maintain regularly to keep oil and gas clean; Secondly, carbon deposits should be cleaned every 20,000 kilometers (without disassembly and cleaning); Finally, pay attention to driving habits, avoid idling for a long time, avoid turning off the engine immediately after driving at high speed, and avoid driving at high speed immediately after starting, and control the shift timing at around 2000-3000 rpm.

After carbon deposition, the method of disassembly-free cleaning is usually adopted, and when it is serious, the method of uncovering the cylinder head to clean the valve is adopted.

How to judge whether the engine should clean up carbon deposits?

Clean the accelerator regularly for 20,000 kilometers, replace the spark plug regularly for 40,000 kilometers, and maintain it regularly! Vehicles are often pulled down at high speed, without too much carbon deposition and without cleaning! If there is something wrong with the car, ask the car master. 4S shop professional technician, 10 minutes to solve.

How to judge whether there is carbon deposit in the engine?

Theoretically, as long as the engine works, there will be carbon deposition. As long as it's not serious, I personally suggest not to clean it. Once you start in road trip, it's no problem to take the expressway.

How to judge whether there is carbon deposit in the car?

The detection of engine carbon deposit is difficult to grasp, professional and uncertain, mainly in the following ways. 1) disassembly method is relatively direct, but it costs labor and money, and the assembly accuracy of modern cars is very high. Disassembly and assembly will damage the engine performance, so this method is generally not used except in the case of serious carbon pollution. 2) Phenomenon analysis method is based on the decline of engine performance, which requires experienced maintenance personnel to analyze the location and degree of carbon pollution. 3) Dismantle the spark plug and fuel injector with an endoscope, and observe the carbon deposition in the intake pipe and combustion chamber with an endoscope, but it may still cause damage to the parts during disassembly and assembly. 4) Computer detection method (1) Use a computer to detect the voltage of the oxygen sensor. Under normal circumstances, the working voltage of the oxygen sensor should change between 0.3-0.7V If the range of voltage change increases (for example, to 0.2—.0.8V), it indicates carbon deposition pollution. The greater the voltage change, the more serious the carbon pollution. This method can only be applied to closed-loop controlled cars. (2) Check the electronic throttle opening. Under normal circumstances, the throttle opening at idle speed should be 1-2 degrees. If the throttle opening is above 3 degrees when idling at room temperature, it means there is carbon pollution. (3) Check the drift of CO and HC in tail gas emission. Under normal circumstances, when the throttle changes, the emissions of CO and HC should be relatively stable. If the drift is large, it means that the three-way catalyst has carbon pollution.

How to judge whether the engine should clean up carbon deposits?

General car driving more than 30 thousand kilometers, there will be obvious lack of power. The increase in automobile fuel consumption is probably caused by excessive carbon deposition in automobile engines. You should consider checking whether it is necessary to remove carbon deposits from cars.