Causes and solutions of Volkswagen engine abnormal noise 20

The common causes of abnormal noise of automobile engine are as follows: 1. Engine knocking. The phenomenon is the abnormal sound of the engine making a "bell".

The engine knocks on the cylinder, mainly because of the sound caused by the piston skirt hitting the cylinder wall when the engine is running. It is usually due to poor lubrication conditions. The solution is generally to replace the four sets of the engine.

2. Abnormal sound of intake and exhaust system. For example, an air intake manifold leaks a noise that occurs when idling and intensifies as the engine speed increases. 3. The engine has a "hissing" noise, which is likely to be caused by a problem with the cooling system, resulting in overheating of the engine.

4. The engine has a "squeak" abnormal sound, especially when the air conditioner is turned on. In this case, it is likely that the belt of the engine is slipping. 5. The engine has an abnormal sound of "clicking", which is likely to be carbon accumulation in the engine.

It is recommended to use high-grade gasoline. In reality, there are many types of abnormal engine noises in automobiles. For example, the abnormal noise of the engine during rapid acceleration, the abnormal noise of the engine during cold start, the abnormal noise of the engine in the idle state, etc., should be analyzed differently in each case.

There is a difference between the reading of the water thermometer pointer and the actual temperature In some models of FAW-Volkswagen and SAIC-Volkswagen produced after 2003, the engine water temperature gauge in the dashboard is the same. When the air conditioner is turned on in high temperature weather, the idle speed is unstable, the speed fluctuates too much, the rapid acceleration is weak, and the engine has abnormal noise; When the hot car is turned off for ten minutes and then started.

I can't pinpoint the exact cause of the abnormal engine noise in the Volkswagen car. Abnormal noises can be caused by a variety of factors, such as friction, wear, breakage, or corrosion of mechanical parts. It is recommended that you seek help from a professional car repair shop in time and have it inspected.

Perhaps the adjusted valve clearance during maintenance has changed or been improperly adjusted; The valve adjustment screws are worn and skewed, the lock nut is loose, or the valve clearance is too large or inconsistent.

On the issue of abnormal noise, it is difficult for ordinary car owners to distinguish which ones are fault 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.

How to identify the sound of a car:

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 made by the dry friction of the bearing, and the "click" sound similar to the small hammer hitting the concrete 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. According to the impact on the performance of the car, the abnormal noise (abnormal noise) carried by potato liquid can be divided into slight noise, general noise and malignant noise.

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 the abnormal noise of the car, attention should be paid to creating good auscultation conditions, trying to eliminate the interference of other noises, using screws or other metal rods as stestological instruments to contact the sound parts to amplify the sound, or using a single cylinder to cut off the fire to reduce the sound, so as to meet the needs of diagnosis. The auscultation site should be kept quiet to minimize human interference.

The causes of abnormal valve noise are: 1. The hydraulic tappet has a gap or serious wear; 2. The oil level of the crankcase is too high or too low; 3. The tappet is dirty; 4. The valve spring seat is worn and grooved, and the valve stem and conduit are worn; 5. The oil is thinner and the oil is replaced with the appropriate viscosity; 6. The oil pressure is too low or too high. The way to deal with valve squeak is as follows:

1. Remove the cylinder head; 2. Grind the valve, check the spring elasticity of the valve, and readjust the valve clearance. The function of the valve is to be responsible for inputting air into the engine and exhausting the exhaust gas after the combustion fluid is depleted, which is divided into intake valves and exhaust valves according to the engine structure.

1. There is an abnormal sound in the engine, and there will be more possibilities for abnormal noise in the engine compartment, and most people also judge that it is the abnormal noise of the engine compartment based on the sound, which is usually a metal screeching sound or a howling sound.

Solution: The abnormal engine noise indicates that the technical status of a certain mechanism of the engine has changed. It is mainly caused by excessive wear and tear of some parts or improper assembly and adjustment.

Some abnormal noises can still predict that the engine will be damaged accidentally, so when the engine has abnormal noise, it should be repaired in time to prevent the fault from expanding.

It should be reminded that if it is an abnormal noise in the engine, most of the owners will not be able to solve it by themselves, and it is best to send it to the factory for maintenance.

2. There is an abnormal sound in the gearbox, if there is a "rustle" sound inside the gearbox during driving, and there is no more after stepping on the clutch or accelerator, there will be a sound similar to whistling when changing gears.

Solution: There are many transmission parts, and the reasons for the sound are more complex, so we should pay attention to whether it is related to a specific speed, such as some planetary teeth that sound at about 50km h.

Whether it is related to certain gears, which is very important for judging the failure of the transmission, if a certain gear sounds, it must be related to the components that affect the transmission of the gear; If all gears sound, it is often a common meshing gear shaft failure or a lack of fuel in the transmission. Whether it is related to specific actions, such as adding and decreasing gears, starting, rapid acceleration, sharp deceleration, turning, etc., are all effective hand early signal segments for judging abnormal noises, among them, changing speed and direction are particularly important for judging rear axle faults.

If the abnormal noise of the transmission is obvious, it is recommended to send it to a professional repair shop to check the faulty parts, and then replace them.

3. There is an abnormal sound in the wear and bend, and there is always some abnormal noise in a certain part of the body when driving and stepping on the accelerator or brake, the sound is not loud, and it does not affect normal driving, but it always makes people worry a little about the failure of the body.

Solution: The abnormal noise of the door is mainly caused by the lack of lubrication, but it is necessary to judge whether it is the position of the door hinge or the glass regulator, door lock mechanism, handle mechanism, etc. inside the door. In the case of door hinges or limiters, special door hinges and slide grease can be used, while special door attachment grease is used for lubrication of glass regulators, door locking mechanisms, handle mechanisms, etc. inside the door.

In terms of brand selection, try to choose the commonly used brands in 4S stores, such as German Marty, Kluber, Tiger Head Hotolube, Fox, etc. It is not advisable to use engine oil or ordinary butter, it will freeze in winter, and the harmful smell will affect your health.

When an engine fails, it often makes an unusual sound. First of all, according to the type of sound, determine whether it is a normal ** sound hitting sound or an abnormal action hitting sound. According to the characteristics of the abnormal sound, the cause is found and eliminated in combination with the structural principle.

The solution to the problem of abnormal engine noise is as follows: 1. Abnormal noise caused by rough engine work. The abnormal noise is caused by the rapid injection time, so the feed advance angle must be readjusted; 2. There is a certain pattern of abnormal engine noise, sometimes knocking on the cylinder, sometimes firing the gun.

At the same time, it is also accompanied by unstable engine speed and intermittent emission of black smoke. This uneven abnormal sound is caused by the injector dripping diesel fuel, and the maintenance of the injector should be carried out when this phenomenon occurs; 3. The exhaust pipe is accompanied by continuous shelling sound when exhausting, and the black smoke is discharged, and the exhaust pipe is overheated and it is difficult to start. At low speeds, the shelling was mitigated.

This squeak is caused by the late injection time, and the feed advance angle must be adjusted immediately.