22 new Sylphy classics have abnormal noise when driving at low speed.
First, the common problems of automobile abnormal noise, it is difficult for ordinary sock owners to distinguish which are faulty abnormal noises and which are reasonable abnormal noises. When I went to the garage to check the vehicles with abnormal noise, only nearly 20% of the vehicles really had problems. There is a difference between models equipped with turbocharged engines; Luhe vehicles with engine guards may also produce noise due to friction; Some car owners may mistake reasonable abnormal noise for vehicle failure due to the lack of mechanical driving knowledge after coming into contact with different cars. Therefore, learn to distinguish the abnormal sound of cars and avoid wasting time and energy.
Second, the identification method of automobile noise:
In practical work, due to the limitation of working conditions, it is difficult to measure automobile noise with special instruments, and only the noise judgment in daily life can be used to describe and compare automobile noise. For example, the "clanging" sound of the beam caused by the friction between bearings and socks, and the "clanging" sound similar to a small hammer hitting the mud floor of the water shed caused by excessive valve clearance.
1, correctly distinguish normal noise from abnormal noise.
The vibration existing in the working of various automobile mechanisms will produce various noises. However, the sad voice doesn't mean that the car is out of order. In order to avoid unnecessary disassembly, normal noise and abnormal noise must be distinguished first. The normal vibration sound of each system component (such as the noise on the engine surface), the impact sound of gears during gear shifting, the intake and exhaust sound with gas as the working source, and the gear meshing noise are all normal noises.
2. Abnormal noise can be divided into slight noise, general noise and malignant noise according to its influence on automobile performance. Slight noise, such as the flashing sound of high-voltage electric socks, slight looseness of rolling and braking bearings, etc. Generally, the acoustic modulus is small, the wear degree of parts is not great, and there is no obvious change for a long time. This kind of fault can maintain the normal running of the car without repair.
3, in the diagnosis of abnormal car noise, should pay attention to create good auscultation conditions, try to eliminate the interference of other noise, so as not to affect the accuracy of judgment.
It is best to amplify or reduce the sound consciously, that is, use a screwdriver or other metal bar as a stethoscope to amplify the sharp sound of the reed, or use a single tube to cut off the fire to reduce the sound to meet the needs of diagnosis. The beam field of auscultation should be kept quiet to minimize the interference of human factors.
Third, the source of abnormal sound:
Abnormal sound source 1: storage compartment. I believe that most car owners have no habit of sorting out storage compartments. The storage compartment that has not been sorted for several years after the car and the owner bought the password key is full of messy items. In this case, no matter where the car goes, as long as the engine breaks down, the items in the storage compartment will "jump" with the engine, and the abnormal sound you hear is probably caused by the vibration of the items in the storage compartment.
Abnormal sound source 2: transmission mechanism. In fact, the steam-excited Tantan car will only make a slight abnormal noise if it fails, but how to judge whether the abnormal noise of the car is a fault or a normal phenomenon? It's actually quite simple. You just need to observe that if the noise becomes louder when the speed increases, it proves that there is something wrong with the automobile transmission system. The most effective solution is to see if there is a puncture in the car tire. If so, I suggest you go to a regular car 4S shop for maintenance.
The reed makes abnormal noise, and the excitation source 3: abnormal noise outside the car. If the abnormal noise you hear comes from outside the car, first check whether the doors and windows of the car are normal and see if there is anything in the trunk. Many times, the collision of objects in the car will also make the driver hear voices, so calling a car is a clever obstacle. In addition, check whether there are sundries around the wiper, and clean them in time if there are any, so as not to affect the normal use of the wiper.
Abnormal sound source 4: pulley. If it is found that the car will make a "cough" sound from time to time during driving, everyone should check whether there is any problem with the pulley of the car when the reed spike is balanced. You should know that the service life of automobile pulleys is about eight years. If the car pulley in the carport has not been replaced for more than eight years, it will make a good sound of "cough" in the cold winter. If the pulley needs to be replaced, Bian Xiao suggested that Daiwa and Daiwa should go to a regular automobile 4S shop to replace the lead pin. Don't do it yourself, or improper operation will cause damage to the car.
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