What are the diagnosis methods of automobile faults?

There are many ways to diagnose automobile faults. Either way, you must have certain professional knowledge and work experience, and master the structure and service life of the vehicle. Common simple methods for diagnosing automobile faults are as follows: touch method. Such as parts heating, loosening, high pressure tubing pulsation, etc. Feeling method. For example, the direction of the car deviates, the turn signal light does not light up, the exhaust pipe emits black smoke or black smoke, and the tire bursts. Explore methods. If one cylinder of the engine is not working normally, it can be found by cutting off the fire and oil one by one. Comparative method. Uncertain faults, such as abnormal cylinder operation, may be the cause of the spark plug (or injector), but when uncertain, a new spark plug (or injector) can be replaced and compared with the original spark plug (or injector). If the fault is eliminated, it can be confirmed that it is a spark plug (or injector) problem. ? The way to listen and walk. The running sound of the engine can be directly recognized by ears, and when the sound is mixed, it can be analyzed by auscultation equipment. When auscultating, you can change the rotation speed or keep a certain rotation speed for diagnosis. For the diagnosis of chassis transmission system fault, it should be judged when the car is running, or the driving wheel should be lifted off the ground and the speed should be changed during diagnosis to determine the faulty parts or parts at different speeds. Test method. For example, there are many factors that cause this kind of fault, and it is difficult to solve it by empirical method or general method. This requires special tests and instrument inspections to find out the reasons and then eliminate them.