Reader Wu asked: my car has been used for six years, but recently found that when the car is running, the engine speed is relatively high, how to deal with it? Reply: for this kind of phenomenon, first of all, may be the problem of the clutch, the use of longer time wear and tear, if now feel the power and not too much change, then can continue to use, if there is a change, you need to change the clutch kit. Secondly, it may also be the instrument itself problem, that is, the instrument instruction is not allowed. Reader Mr. Tang asked: Recently, when I was using a car, I noticed that there was black smoke coming out when the car was speeding up. What is the reason for this? Reply: this may be the reason for the intake pressure sensor. It is recommended to use the maintenance diagnostic apparatus to check the control system. There is also the reason for fuel pressure. The fuel pressure gauge is used to carry out the oil pressure test. If too high, it will cause the above phenomenon. When the car changes the fuel pump, it will also appear black smoke when its model is wrong. The other is oil leakage, that is, oil leakage from fuel injector, resulting in too much mixture. If the ignition time is too late, it will also cause dynamic degradation and poor fuel economy. At the same time, it will cause bad combustion of vehicles. The reader, Miss Huang, asked: when he used the car in the near future, he saw the throttle dirty and cleaned the throttle of the throttle on his own. But after the fire, it found a different noise. What is the reason for this? Reply: the throttle body needs to be removed and cleaned. Cleaning in the car is easy to damage the throttle, because the electronic throttle body is assembled now, and after cleaning, it is necessary to use the computer for basic setting and re matching to the normal use, so it is suggested to be cleaned in the special shop later. If the voice is obvious and the idle speed is not stable, it is recommended to go to the store for examination. Mr. Tian asked: when the car reaches 60 speed, it can hear the whistle of the differential. What is the reason? Response: in this case, the first need to judge what causes the abnormal noise, if it is due to abnormal wear caused by abnormal wear of the gear or bearing in the differential, then the failure to repair will lead to more and more serious wear and tear, more and more obvious at the same time.