What happens when the Audi car changes the timing belt and makes an abnormal sound? Thank you

Hello: Regarding your question, when the Chevrolet Levair travels to 60,000 kilometers, the timing belt assembly is replaced, and the water pump needs to be replaced when the timing belt is replaced, and the total maintenance cost is about 1,600 yuan.

On the issue of abnormal noise of automobiles, it is difficult for ordinary car owners to distinguish which ones are abnormal noises and which ones are reasonable abnormal noises. Only nearly 20% of the vehicles that went to the repair shop to detect abnormal noises really had problems. In the case of a turbocharged engine, there is a must be a difference between the sound and the sound of a naturally aspirated engine; Models with engine guards may also make noises due to friction; After some car owners come into contact with different cars, it is likely that they lack their own understanding of mechanical knowledge, so they can distinguish the abnormal noise of the car and avoid wasting time and energy.

Second, the identification method of car noise:

In practice, due to the limitations of working conditions, it is difficult to measure the sound of the car with special instruments, and the sound of the car can only be described and compared with the judgment of the sound in daily life. For example, the "rattle" sound caused by the dry friction of the bearing, and the "click" sound similar to the small hammer hitting the cement floor caused by the excessive valve clearance.

1. Correctly distinguish between normal and abnormal sounds.

The vibration of each mechanism in the work of the car will emit a variety of sounds, but the sound does not mean that the car is faulty, in order to avoid unnecessary disassembly, we must first distinguish between normal sound and abnormal noise. The normal vibration sound of each system component (such as the noise on the surface of the engine), the impact sound of the gear when shifting, the air intake sound and exhaust sound of using gas as the working source, and the gear meshing noise are all normal sounds. Abnormal noise (abnormal noise) can be divided into slight noise, general noise and malignant noise according to the impact on the performance of the car.

Slight noise, such as the flashover sound of high-voltage electric leakage, the slight loose sound of rolling bearings, etc., the general volume is small, the degree of wear of the parts is not large, and there is no significant change for a long time, and this kind of fault can still maintain the normal operation of the car without repair.

3. When diagnosing abnormal noise, attention should be paid to creating good auscultation conditions and trying to eliminate the interference of other noises, so as not to affect the accuracy of judgment.

It is best to consciously amplify or reduce the sound, that is, use a screw or other metal rod as a stestological instrument to contact the sound part to amplify the sound, or use a single cylinder fire cut-off to reduce the sound to meet the diagnostic needs. The auscultation site should be kept quiet to minimize human interference.

This phenomenon is often seen. I used to have a repairman. The customer requests a belt to be replaced.

At that time, the engine did not make any noise. When he finished changing the timing belt. There was a beep after starting.

I asked the repairman. The sound came there. He said he didn't know.

I said that there was no sound in front of the belt when the car was realigned. And when you change the timing liquid blind with the belt, the fingers will make a noise. It's so hard that you can't praise the gods.

He still didn't know.

Or the timing belt is not installed properly. The tensioner needs to be adjusted by turning the water pump, and if the tensioner is not adjusted properly, there will be a sound. Mine is like this, the first time the 4S shop map is trouble-free without adjusting the water pump and directly installing the timing belt, which is very noisy.

I reinstalled it in a different place, and it was normal.