Why are there black stains on the exhaust pipe?

It is normal that there is black dirt on the exhaust pipe of Pacific Auto Network. Usually, the fuel of a car is mainly gasoline. After a long time of use, there will be black dirt on the exhaust pipe. The pollution degree of exhaust pipes of different models is completely different.

There are generally three situations. The first situation is that the spark plug is not working well, because if the spark plug is not working well in the cold start condition, the mixture will not burn fully, thus emitting a lot of black smoke. The second situation is the problem of the oxygen sensor. If the engine is used for a long time, all aspects of performance will deteriorate, resulting in the car can only spray gasoline, can not burn with air, so it will produce a lot of black smoke. The third situation is that the starting time and ignition time of the car are wrong, which will lead to the incomplete mixing and combustion of oxygen and engine oil. In other cases, there are also problems such as temperature sensor damage and nozzle blockage. If you find the above situation, you must deal with it in time, and you should also pay attention to these problems in normal maintenance.

There are three solutions. The first way to clean the throttle is to directly remove the engine decorative cover, remove the throttle and clean it with special cleaning agent, and then clean it with cotton cloth. This cleaning price is still very different from the price of 4S stores. If you can operate it yourself, it is recommended to clean it yourself. The second is to clean up the carbon deposit inside the engine, and the third is to clean up the carbon deposit in the oil circuit. If you have no experience, I suggest you go to the repair shop to deal with these two solutions. (Photo/Text/Photo: Pacific Auto Network Zou Ting 1)