Automobile maintenance knowledge

Abnormal car noise is a headache for many riders. The more you check the information, the more you think there is something wrong with the car. Today, I will tell you how to deal with the abnormal sound of your car.

1, abnormal sound after flameout

It is normal for a car to produce abnormal noise after flameout, which is mainly caused by the following two aspects: First, the exhaust pipe noise, when the engine is flameout, the temperature drops. The exhaust pipe and the three-way catalyst have different thermal expansion coefficients and different contraction degrees, so metal collision will produce sound. The second is the sound of the engine exhaust fan. After the engine is turned off, the engine fan will make a sound before it stops working completely.

The above is a "false abnormal sound", not a fault. However, under the normal condition of flameout and cooling, the car still makes abnormal noise, so we have to find out the reason.

2. Abnormal sound of brake pads

Whether you just put on brand-new brake pads or encounter flood season (as well as the ice and snow weather after cooling), you may hear sharp friction when braking.

This kind of "abnormal sound" is normal in most cases: either it is the sound produced when the brand-new brake pads are running in with the brake discs; Either the brake pads are attached to the sediment, and the sound is generated by pedaling friction.

3. Abnormal sound of body/door

When we are driving in rough road conditions, the door sealing strip will produce abnormal sound due to the twisting of the vehicle; Or the tire rubs against the ground and produces strange sounds (tire noise), which is a normal phenomenon.

4. Engine noise at high speed

When driving at high speed, the engine speed is much faster than usual, and the noise will be louder than normal driving, so don't worry too much. But if the frequency of abnormal sound is uneven, we should be vigilant.

5. Abnormal chassis noise

When the road surface is complex, the suspension parts of the chassis will make abnormal noises, such as the rubbing sound of rubber sleeves and the impact sound of parts, so it is necessary to check whether the parts are damaged or aging.

6. Abnormal fetal noise

In addition to the reasons of road conditions and speed, it should be noted that the tire noise of the vehicle with tire repair may be greater; If the tire is patched or the tire is stuck in the car by a foreign object, abnormal noise may also occur. In addition, when the engine, gearbox and other important parts are found to have obvious, irregular and unexplained abnormal sounds, go to a professional testing station for physical examination.