May I ask, what is the cause of abnormal noise in the car engine?

There are generally the following reasons for abnormal engine noise:

1.Loose fasteners.

During the operation of the automobile engine, the mechanical parts will vibrate, and over time, some parts will loosen, and the collision of parts will make an impact sound. For example, the flywheel fixing bolt is loose, the connecting rod bolt is loose, etc.

2.Individual parts are deformed and damaged.

It is mainly due to the abnormal sound caused by the deformation and damage of a certain component, such as the knocking phenomenon caused by the bending of the connecting rod, the broken valve spring, the broken crankshaft, etc.

3.Improper assembly, adjustment, or repair.

In the assembly or maintenance of automobile engine equipment, improper application of technology will lead to abnormal noise caused by misalignment of the fitting gap of the parts. For example, the piston pin assembly is too tight, the valve clearance is not adjusted properly, etc. In the standard acceptance process of automobile assembly quality, the mating clearance is a very important indicator.

When data such as lubrication, temperature, load, and speed are kept within a certain range, the squeak will increase with the increase of the mating clearance. Some moving parts of the engine will spontaneously combust and wear out with the running time, causing the gap to increase beyond the range and cause abnormal noise.

4.Poor lubrication.

In order to ensure the long-lasting and smooth operation of automobile engines, lubricating oil is often used, and the internal lubrication system can realize rapid lubrication, real-time cooling, timely cleaning and sealing of mechanical parts, while effectively preventing rust. When the data such as clearance, temperature, load, and speed are kept within a certain range, the thickness of the lubricating oil film will increase with the pressure of the lubrication system and the quality of the lubricating oil. Therefore, the good quality and appropriate pressure of the lubricating oil will form a good lubricating oil film on the surface of the machinery, which can effectively alleviate the mechanical impact and reduce the occurrence of abnormal noise.

However, if the lubricant film is not formed enough or too thin, the wear rate will be increased and the engine sound will be more pronounced.

5.The temperature is too high.

Some abnormal noise faults have a great relationship with the temperature of the engine, and in the diagnosis, special attention should be paid to whether the hot state of the engine is in the accessories with a large thermal expansion coefficient. For example, when the piston strikes the cylinder, when the engine is started, there will be a noticeable abnormal noise, and once the temperature rises, the sound will weaken or even disappear. In this regard, the response of the diagnostic cold knock should be carried out in a low temperature environment.

Temperature has little effect on machinery with a small coefficient of thermal expansion, such as the main bearing of the crankshaft, the ring of the connecting rod bearing, etc.

There is a sizzling sound in the engine, there may be a problem, the engine is overheating, check the cooling system. The exhaust system is clogged, the vacuum tube is leaking, or it is broken. The causes of hysterical sound problems in the engine can be divided into, air filter, spark plug, ignition wire, gasoline, gasoline filter, vaporizer, oil pump and other problems.

Because the gearbox is faulty or the engine is broken, or it is possible that the steering wheel is broken, the tires are abnormal, and the brakes are abnormal, so there will be abnormal engine noise.

There are many reasons that will make the engine abnormal noise, you can go to a professional repair shop to test it to see if there is any problem with the car engine, so there will be abnormal noise.

1. The cylinder is seriously worn and grinds the cylinder, 2. The ignition timing is adjusted, 3. The piston ring is not suitable, and the 4. The piston end gap is too large and needs to be adjusted.

The mechanical abnormal noise is mainly caused by the impact and vibration caused by too large the moving mating gap or damage to the mating surface, and during operation. The abnormal combustion noise is mainly caused by abnormal combustion of the engine. The aerodynamic abnormal noise is mainly caused by the vibration of the air flow in the intake and exhaust of the engine and the fan in operation.

Squeak and squeak are related to engine speed, temperature, load and lubrication conditions.

Therefore, in order to accurately determine the cause of abnormal engine noise, it is necessary to conduct a professional inspection of the car. In addition, the situation varies depending on the model.

If the engine sound is slightly louder every time it reaches 1500 rpm, and it is normal to reach this value or exceed this value, it may be that there is something wrong with the engine's holding system. You can try to adjust the ignition time first.

Cool weather, clutch plates, oil lamp problems.

There are a lot of abnormal noises, depending on what kind of abnormal noise you are, whether it is idle running, abnormal noise or abnormal noise when driving.

1. The existence of most common abnormal noises of the engine depends on the speed state of the engine. Abnormal noise only exists when running at idle or low speed; The sound is disordered when it is maintained at a certain speed, and it makes a brief sound when it decelerates sharply; Abnormal noises occur when the engine accelerates sharply, and the sound persists when running at high speeds.

2. The abnormal noise failure of the engine is often obviously related to the working cycle of the engine, especially the abnormal noise of the crank connecting rod mechanism and the valve mechanism are related to the working cycle. Usually, the sound caused by clearances unrelated to the duty cycle is mostly due to faulty engine accessories; If there is a continuous metal friction sound emitted by a mechanical part that is not related to the duty cycle, it can be considered that some rotating part is faulty.

3. The problem of the filter collector, the rubber ring is not well sealed, so that the oil pump cannot suck up the oil normally and suck a lot of air when it is working, and the engine system is not lubricated enough, especially the hydraulic tappet part of the valve, which makes a metal knocking sound; The filter collector is clogged and does not properly draw oil into the engine lubrication system, resulting in poor lubrication.

4. The oil pump is not working properly and cannot suck the oil in. Poorly lubricates the engine lubrication system.

5. The valve hydraulic tappet is partially damaged, and the related system does not work properly for a long time, resulting in insufficient lubrication of the parts and causing damage.

Modern car engines are of high quality and there are very few squeaks anymore. As long as you change the oil and three filters every 5,000 kilometers, you can run 1 million kilometers without a problem. But if the oil is never changed at the factory, the engine will be scrapped for 30,000 kilometers.

The abnormal noise of the engine is caused by too much wear and tear and the clearance exceeds the standard: the large watt noise and the crankshaft bearing clearance exceed the standard. The small wattle sounds, and the connecting rod bearing clearance exceeds the standard.

The cylinder knocks and the piston and cylinder clearance exceeds the standard. The pin ringing is an excess of the piston and piston pin clearance. The cylinder sounds, the connecting rod bends and the piston clearance exceeds the standard.

The timing gear rings when the timing gear clearance exceeds the standard. The camshaft bearing rings and the camshaft bearing clearance exceeds the standard. The sound of the valve foot is caused by the excessive clearance of the valve foot.

The cylinders of the engine work unevenly, the slow car (idling) engine will shake, the cold car will be more powerful, the temperature will come up, and it will not be audible after acceleration, and the cylinder pressure of each cylinder can be measured, or the spark plug can be replaced. Remember: the internal combustion engine, three treasures:

Oil foot, electric rod, compression is good. If one of the three things does not work, the cylinder engine will not go well, and the engine will be uneven.

If the engine of the car has an abnormal noise, there should be some loose reasons, or the parts inside have been aged, and it is best to drive the car to an experienced mechanic for diagnosis, which may get a better cause.

The cam is worn excessively, and the tappet jumps during operation; 2.Excessive valve clearance due to wear or improper adjustment of the valve stem end and adjustment screw or rocker arm causes the swing arm head of the overhead valve to collide with the top of the valve; 3.excessive carbon deposition in the valve guide; 4.

The valve spring seat falls off; 5.Hydraulic tappets or tappets are damaged.

There can be many reasons why a car engine may have abnormal noise, and here are some of the common ones:

Poor lubrication: If there is a problem with the lubrication system of the automobile engine, such as oil pump failure, excessive dirty oil, etc., it will lead to the failure of the engine components to get sufficient lubrication in the friction movement, resulting in friction sound and abnormal noise.

Piston knocking cylinder: If the cylinder inner wall of the automobile engine is worn or the engine working temperature is too high, it will make the piston and cylinder poorly matched, resulting in the abnormal sound of the piston knocking cylinder in the engine. At the same time, problems with the cylinder gasket, piston rings and other components will also produce such abnormal noises.

Flywheel wear: When the gears and clutch discs on the engine flywheel are worn, noise and squeak will occur. In addition, if the flywheel is loose or foreign objects enter, it can also cause abnormal noises.

Excessive gear clearance: The gearing system in a car engine is an important component that transmits power from the engine to the wheels. If the gears are worn or the clearance is too large, noise and squeaks will occur.

Ignition system problems: The ignition system of automobile engines mainly includes ignition coils, spark plugs, high-voltage wires, etc. If these parts fail, the engine will fail to ignite or even start.

In some cases, a problem with the ignition system can also cause the engine to make abnormal noises.

In short, abnormal noise in a car engine may be the result of a combination of many reasons. If you notice abnormal noise, it is recommended to contact a professional car maintenance personnel immediately for inspection and repair. And the maintenance of Hu Yin can avoid the aggravation of the problem and improve the safety of driving.

There can be a variety of reasons for abnormal noise in a car engine, and the common causes include the following:

Friction noise: Noise may occur due to friction between various components inside the engine, such as piston rings, valves, crankshaft bearings, etc., especially during start-up and high-load operation.

Valve noise: When there is a problem with the intake or exhaust valve of the automobile engine, such as valve stem or rocker arm wear, valve stem clearance is too large or valve clearance is too large, etc., it will cause the valve to open and close abnormally and produce abnormal noise.

Compression noise: Compression noise can be caused by low cylinder pressures in a car engine or leaks inside the cylinders, such as cracks in piston rings, valve guides, or cylinder walls.

Boiler noise: When some parts in the intake or exhaust system of the automobile engine are damaged, such as the intake pipe, exhaust pipe, muffler, etc., boiler noise will be caused.

Drivetrain noise: When there is a problem in the drivetrain of a car, such as the failure or wear of components such as transmission and clutch, it can produce abnormal noise.

When there is an abnormal noise in the car engine, it is best to contact a professional car maintenance personnel for inspection and repair in time to avoid more serious consequences due to the problem not being dealt with in time.

If you hear a buzzing sound when you press the throttle to accelerate, the first thing to consider is the gearbox. The higher probability is the sound of the gearbox bearing wearing, this is because there is too little lubricating oil and too much friction in the gearbox, so it needs to be refueled. If you find that the throttle is buzzing, the speed is high when accelerating, but the speed is not fast, it is caused by clutch slippage, and the clutch kit needs to be replaced.

In addition, if there is noise during braking, the braking system is submerged and needs to be replaced as soon as possible. Here's why:

1. The engine oil is not completely lubricated to the engine parts, and the new engine oil can be evenly lubricated to the engine parts after running for a certain time.

2. If it is not good after a certain period of time, it may be that the wear is serious, and then the inside of the engine is cleaned to make the wear gap larger.

3. The gap between the seams is large, the sealing is not good, the engine condition will deteriorate, and there may be a loud sound, so it is recommended to go to the repair shop for inspection.

4. If you don't pay attention to the maintenance of Wang Luyang, it may be caused by too much carbon deposit in the machine (too much carbon deposit in the engine, too much carbon deposit in the throttle, too much carbon deposit in the spark plug, etc.), go to the maintenance shop to clean it up.

5. It is also possible to filter the transmission poorly (most commonly.

The causes of abnormal noise in automobile engines are: engine throttle carbon deposit, exhaust system blockage, spark plug failure, muffler problem, cooling system failure. The role of the engine is:

The heat energy of gasoline and diesel is converted into mechanical energy by expanding the gas after combustion in the sealed cylinder, and pushing the work done by the piston.

The system components of the engine are:

1. a gas distribution mechanism; Messy shirts.

2. a crank connecting rod mechanism;

3. an ignition system;

4. a cooling system;

5. Lubrication system ruler qing;

6. starting the system;

7. Supply system.

The maintenance method of the engine is:

1. Use qualified engine oil;

2. Use qualified coolant and antifreeze;

3. Clean the scale of the water tank regularly;

4. Clean up the carbon deposits of the engine regularly;

5. Regularly replace the three filters of automobiles;

6. Maintain a reasonable speed or sleepy gear.

There can be a variety of reasons why a car engine makes an abnormal noise, and here are some of the common ones:

Wear and tear of parts and components of automobile engines: such as crankshafts, connecting rods, piston rings and other components are seriously worn, which will cause friction and collision between metals, resulting in abnormal noise.

Lubrication system failure of automobile engine: If there is a problem with the oil pump, oil filter and other components of the automobile engine, it will lead to insufficient oil or poor oil quality, which will lead to increased friction and abnormal noise of engine parts.

Ignition system failure: If the ignition system of the car fails, such as spark plugs, high-voltage wires, ignition coils and other components, it will lead to insufficient combustion of the car engine, resulting in abnormal noise.

Air intake system failure: If the air intake system of the car engine fails, such as the intake pipe, throttle, Min Ji air filter and other components, it will lead to poor airflow, brightness and width, which will cause abnormal noise of the car engine.

If the engine of the car is abnormal, it is recommended to go to a professional car repair shop for inspection and repair immediately.