What should I pay attention to when the cleaning nozzle fails?
The injector is divided into front and rear parts, and the front and rear parts are a riveted whole. The back end is engineering plastic, the front end is metal nozzle and the inside is electromagnetic needle valve. The electromagnetic needle valve is usually closed, blocking the oil path to the nozzle. When receiving the driving pulse from ECU, the needle valve is pulled up by electromagnet to open the oil path, so that the high-pressure oil provided by the oil pump is sprayed from the nozzle. To put it bluntly, cleaning is to simulate ECU to give the nozzle a constant drive to make it open for a long time, and then use mixed oil with cleaning ability to clean the nozzle at high pressure before and after.
There are two dangers. First, the ECU gives pulses, with cooling time in the middle, but the constant drive does not. Therefore, the current requirements are extremely strict to prevent overheating and burning. Because the coil is short-circuited in DC equivalent, it is only a matter of time before the working current can not be strictly controlled. Second, what is the essence of blocking? Some plugs and cleaning agents are natural abrasives, which do great harm to nozzle micropores. Although cleaned, the physical parameters of micropores have also changed, which is inevitable.