When the car is on the road, we can hear a lot of sound in the car. Of course, the more high-end cars are better in controlling the noise in the car, but some noise is unavoidable and should not be avoided. Because we can judge all kinds of situations from various voices. Some of the noises we can hear are reasonable noises, some of them are abnormal noises due to the malfunction of the vehicle. So what is the noise that normally produces when the car is driving? 1, different road conditions will cause the car body structure to produce different jolt and vibration effects, thus making a certain noise; 2, different automobile tires and the ground contact with the ground contact noise and air vibration noise, that is, the so-called 3, the noise produced by the car body through the atmosphere is called the so-called wind noise; 4, when the car runs, the engine will have the sound vibration, exhaust, air intake sound; 5, the car is driven by the transmission system to transmit power, in the transmission process of mutual movement excited The vibration of the hair; 6, when the brake, the brake system and the tire ring between the friction between the sound of the sound; 7, if the car in the use of air conditioning, air conditioning fan will also make a certain sound. All of the above are normal range car sounds, so what does it suggest that the car has trouble need to be repaired? If you can know some of the car's failure sounds, at least you can judge whether to go to a repair factory. If there is a strange and unusual noise when the car is running normally, it needs special attention. Any abnormal sound from a car means that some changes have occurred in the operation of the vehicle. 1. High frequency screech: if your car starts screaming at cold start, it will last for a while. Then you should consider checking the driving belt and replacing it if necessary. Generally speaking, the transmission belt is slippery or the edge is thin. 2, slight metal impact sound: if the engine feels the direction of the engine after the metal is rubbing back and forth, it may be the sound of the mixture of oil and gas in the combustion chamber of the engine. This is often the case if low or unqualified gasoline is used. Pay attention to the coolant temperature to determine whether the engine is overheated. If abnormal, replace the high standard gasoline quickly or increase the zinc alkane value additive. Sometimes, too much carbon in the engine will also produce such abnormal sound. Cleaning the fuel system can relieve symptoms. In a word, such a sound must be eliminated and solved as soon as possible, so as to avoid shortening the life of the engine. 3, gently clasp sound: if the vehicle acceleration will always hear the sound of the engine in the direction of a gently buckle, or drop clada, the sound is not big, but it will continue, but the parking will not sound again. Such a noise usually occurs as the valve clearance is not uniform due to the lack of engine oil or oil filter for a long time. Check the oil first. If there is no shortage, you can only go to the maintenance plant to check the valve clearance or repair the engine. 4, detonation sound: it is often mentioned that the engine detonation, do you know what kind of noise is detonation? Generally, detonation is the sound of a heavy hammer knocking on metal, and it will be accompanied by some engine vibration. Because of the loud noise, it is generally a big problem. Be sure not to insist on driving and stop for repair as soon as possible, so as not to aggravate engine damage. 5, a slight hissing sound: the hoarse sounds like this, you feel the sound of the air, someone will feel the illusion of yourself, or the careless person doesn't notice the sound at all. If the sound is confirmed, it is necessary to consider whether the vacuum tube breaks or the vacuum leakage causes engine loss and low efficiency. In order to find out the cause of the sound, we must check where to leak and observe the source of the sound. 1, a high frequency scream will appear on the brakes: sometimes new brakes scream when they are just changed, but they will soon disappear. If it does not disappear, there will be screams and shrill noises on the brakes. It is necessary to consider whether the installation is wrong or the brake system needs to be repaired. 2, scream when you step on the brakes and stop when you don't step on it: if you step on the brake, there is a scream and the scream disappears when you let go of the brake pedal, and it's clear that your brake should be replaced. Because most of the brake pads are filled with soft metal, if the friction material on the brake pad is about to be polished, the metal layer will be used to alert the warning. 1, obvious rhythmic percussion: if the car accelerates or decelerates, the car will have a bigger sound and a more rhythmic blow, but not at the rest of the time, then check to check whether the tire is normal. If tire rubber is aged, damaged, frothy and worn seriously, this will happen, and there will be some slight vibration. 2, the loud sound: if the car starts to have a huge sound, a bit like an explosion, it is generally the failure of the engine exhaust system, the spark plug delayed fire, resulting in the excessive accumulation of oil and gas mixture in the combustion chamber and the huge noise. In general, cars of older cars tend to have such a sound, but the only thing you can do is to stop at once and find professional maintenance. 3. The sound of a carbazole in the turning of a vehicle: this situation usually appears on a front or four drive car. This clicking sound comes from the steering bearing, although the sound is not large, but it may have potential risks, or as soon as possible.