Carbon deposit refers to a mixture that accumulates on the valve, combustion chamber, and intake pipe of an engine. It is caused by the engine oil not being fully burned. Under the catalysis of high temperature and oxygen, hydrochloric acid and resin-like colloids are formed, which adhere to the surface of the parts, and are further concentrated into asphaltenes and oil coke after high temperature mixture.
How to check carbon deposits in the car?
1.Disassemble the engine. This is intuitive, but takes a long time , and every disassembly as well as assembly of any component will affect its performance and shorten its life.
2.Take off the spark plug or fuel injector and use an endoscope to observe the degree of carbon deposits on the valve. It is very convenient, but an endoscope cost a lot money, not all repair stores are equipped with this equipment.
3.Use a diagnostic computer to read the changes in the oxygen sensor.Generally, the oxygen sensor feedback voltage fluctuates between 0.3-0.7V, and there should be 8 alternations of the maximum value and the minimum value within 10 seconds.Once there is carbon deposits, the feedback voltage of the oxygen sensor will fluctuate greatly, for example, from 0.3-0.7V to 0.1-0.9V. And the center value of this voltage will become larger, and the frequency of change will slow down. It is a technically easy way but the result will be affected by the other failure of the car, thus it requires an experienced mechanic to perform this test.
5 ways to decrease or clean Carbon deposits
1.Fill high-quality gasoline
Impurities such as wax and gum in gasoline are the main components that form carbon deposits. Therefore, gasoline with high cleanliness has a weaker tendency to form carbon deposits. Car owners try their best to refuel at regular gas stations. In addition, some gasoline cleaners can be added appropriately, which can effectively prevent the formation of carbon deposits on the metal surface, and can gradually activate the original carbon particles and slowly remove them, thereby protecting the engine from harm.
2.Don't stay idle speed for a long time
The longer car stay in idle speed, the more time for the engine to reach the normal temperature.the time for the engine to reach the normal temperature will be longer.At the same time, the air flow into the engine become smaller, so that the scouring effect on carbon deposits becomes weak, which will promote the deposition of carbon deposits.
3.Running more at high speed
Use the scour effect of the airflow on the inlet to prevent carbon deposits.Appropriately increasing the speed of shifting is also a similar way. Changing the original speed of 2000 to 2500 conversion can not only effectively prevent carbon deposits, but also improve the dynamics of the car and avoid shifting. Explosion caused by low speed to protect the engine
4.Use fuel cleaning and cleaning additives
When the engine is working, the cleaning agent is sucked into the fuel supply pipeline by the fuel pump along with the fuel. With the flow of fuel, it can not only clean the glue in the fuel tank, the glue on the gasoline pump filter and the glue and carbon deposits on the fuel injector, but also automatically clean the valve and the engine cylinder when the engine is working normally. Carbon deposit.
Because the chemical cleaning components in the cleaning agent have a certain corrosive effect on the rubber fuel supply pipeline, when using this method, you must pay attention to the use cycle, otherwise it will accelerate the aging and corrosion of the fuel rubber fuel supply pipeline.
The cleaning of valve carbon deposits is relatively simple. After the intake manifold is removed, it can be removed manually or soaked with cleaning agents. As for the cleaning of the carbon deposits in the engine cylinders, it is necessary to "make a big move" and remove the cylinder head, timing belt, etc. to clean it.
After the engine is disassembled and reassembled, its power and sealing performance will be inferior to the original factory, so in general, cleaning the carbon deposits in the engine cylinder should not be done frequently. As a last resort, you must also go to a regular repair shop, otherwise the engine performance will be greatly reduced.