What is the reason for the grunting sound in the left rear of the car when it accelerates?

<>Since you're talking about the left rear! I don't want to get rid of the transmission or the front wheels. You this "ringing". Let's see if I can "understand" and come to the conclusion that no. Hehe, since I haven't seen the actual car, let's make a preliminary judgment for the time being:

The left rear part (hey, I don't know what model you are, please ask your boss to make it a little clearer next time).

There is no at low speed: It is because the load of the vehicle is not large, correct, and the load value of the abnormal noise part transmission or coordination working condition is not large.

When the third or fourth gear is there: When the speed gradually increases, the resistance and load in all aspects increase. Hear more clearly and correctly.

Fifth gear is gone: Fifth gear is not gone, but the speed is so fast that you "can't hear". I'm not scolding you, hehe. That's right, too.

In the case of a rear-wheel drive drivetrain, it is recommended to focus on the rear two tires:

a. Due to the fear of audible errors, check the parts of the left and back and right parts of the lower back.

b. Check the tires and rear axle parts, whether the tires are deformed (irregular or the tires are tied with things or mixed with foreign objects such as stones) or the rear wheel bearings are partially worn and lack of oil (lithium grease), sometimes the reason for the deformation of the tires or the new tires can also cause abnormal noise due to various reasons such as wrong patterns and specifications (as you described), which is easy to be overlooked. The rear wheel suspension or bearing part is mainly checked, as well as each rubber sleeve and rubber block, etc.!

c. There are also differentials, oil and gears for the rear drive. (I won't talk about this much, I won't finish it in a day or two).

d. Listen carefully to the abnormal noise, sometimes when the judgment is wrong, or due to wind resistance, it may be the abnormal noise in front.

Maybe I've seen a lot of this phenomenon, but you have to describe the car model clearly and listen carefully to the parts of the abnormal noise.

If it is prodromal, the recommendation is similar to the above, except that item C is missing.

If your car is a bread or something, it should be inside the gearbox. It is recommended that you go to the repair shop to prop up the car with a lift, and then you start the car and let the maintenance master listen below. Find a familiar repair shop.

If you have time to go to the repair shop to check it out, after all, it is good for yourself!

Analysis of the cause of the special noise of the automobile engineEngine oil

If the oil viscosity of the vehicle is too high, it is easy to cause problems in the operation of the engine, and the lubrication effect will be poor, resulting in high engine noise. Therefore, at this time, you should go to the repair shop in time to check whether it is time to change the engine oil, or calculate whether the time for maintenance is up.

Transmission beltsCheck to see if the drive belt is loose, sometimes the belt is loose and can cause the engine compartment to become louder. At this time, the transmission belt needs to be replaced in time.

Water temperature

If the engine is noisy, it is also possible that the water temperature is too high, and it is necessary to see if the water temperature gauge is normal and whether there is smoke coming from the engine compartment.

Phenomenon. Be sure to change the coolant before winter.

The reasons why the engine is very loud: 1. The car may have been used for too long and the parts are aging; 2. If there is carbon deposit in the engine, the carbon deposit can be cleaned up in time; 3. The quality of the oil is unqualified; 4. The temperature sensor is faulty. An engine is a machine that can convert other forms of energy into mechanical energy, including internal combustion engines, external combustion engines, jet engines, and electric motors.

Improving the layout position of the engine air intake system can effectively reduce the inlet temperature and improve the air intake density of the charging engine, so that the engine can output more power on the basis of improving the charging efficiency, and the specific improvement method is to arrange the air intake pipeline of the engine on the cooling water tank on the left side of the engine front-end module.

<> this phenomenon in the engine is related to the coolant, the lack of coolant or the quality of the replaced coolant is problematic, this situation is more likely to occur in the summer when the temperature is hot, which is often called the phenomenon of boiling the pot. This will affect the performance of the car, as well as the service life, in this case, we must pay attention to it and deal with it in time. When there is a lack of antifreeze, it is difficult to find the lack of antifreeze in general inspection, because the vehicle is in a hot state, and the lack of antifreeze in the warm air tank is not easy to see, so it leads to disassembly and maintenance, and the cost increases.

Engine Coolant PrecautionsCoolant is an indispensable part of the engine. It circulates in the engine cooling system to take away the excess heat generated by the engine's operation, so that the engine can run at its normal operating temperature. However, as the time of use increases, the performance of the coolant gradually loses.

Therefore, the coolant should be scientifically tested according to the operation of the engine, and the coolant that can no longer be used should be replaced in time. The thermal efficiency of the engine is only 30% 40% when combusting, and the remaining heat must be taken away in time, and the normal working temperature of the engine with a maximum speed of 4000 r min is 80 90. The normal operating temperature of the engine with a maximum speed of more than 6000 r min is 88 105.

40% of the remaining heat after the engine is done is taken away by the oil, and 60% is dissipated into the surrounding air by the cooling system.

You're a wheel hub that's deformed, and when this happens, there will be a gurgling sound while driving.

Only by replacing the wheel hub and rebalancing the tires can you do it.

In addition, the oil leakage of the shock absorber will also have a gurgling sound, which needs to be checked.

The right front wheel gurgles, whether it has been repaired: see if the wheel screws are loose, and then see if the tires have been pierced into screws and other hard objects, and then take off the tires to see if something fell into the inside when changing the tires, and then look at the bearings. There are also many reasons why the front wheels rattle:

1. Rhythmic screeching This may be a friction sound caused by the gap between the brake pad and the brake disc is too small. 2. Continuous squealing may be the bearing is broken. 3. The continuous dull sound may be a problem with the transmission shaft.

Because what you said is not very specific, you can also experience whether the sound changes when neutral and dragging, if so, it is likely to be the cause of the propeller shaft.

It should be the sound made when the engine is idling, if the sound is loud, you can do the maintenance of carbon deposition, the sound will be much quieter.

1) Suction stroke: the intake valve is opened, the piston tends to descend from the top dead center, and the cylinder volume slowly increases;

2) Compression stroke: the intake and exhaust valves are closed, the piston goes up from the bottom dead center, and the cylinder volume gradually decreases;

3) Working stroke: the intake and exhaust valves are closed, the diesel fuel is sprayed in the form of a mist, and it spontaneously combustifies under the action of high temperature and high pressure, and the piston goes down from the top dead center to drive the crankshaft to rotate through the connecting rod;

4) Exhaust stroke: The exhaust valve is opened, the piston goes up from the bottom dead center, and the exhaust gas after combustion is pushed out by the piston.

The engine is rumbling, it is because there is a lack of oil in the gears, or dust is in, or it is possible that the machine is malfunctioning.

Abnormal noise during acceleration, this situation may be engine knocking, or it may be caused by friction between the lubricating oil and gas valve and the conduit and the hydraulic tappet.

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.

Other causes of abnormal car noise.

1. Abnormal noise only exists when it is running at idle speed or low speed.

The reasons for the sound are: the gap between the piston and the cylinder wall is too large; The piston pin assembly is too tight or the connecting rod bearing is assembled too tightly; The gap between the tappet and its guide hole is too large; The profile of the valve cam is worn; Sometimes, the starter grip comes loose and the pulley makes a sound (noticeable when the speed changes).

2. The sound is disordered when maintaining a certain speed, and a short sound is made successively when decelerating sharply.

The reasons for the sound are: the camshaft timing gear is cracked or its fixing nut is loose; crankshaft breakage; The piston pin bushing is loose; The axial clearance of the camshaft is too large or its bushing is loose.

When the clutch release bearing is damaged, the clutch plate cannot be completely disengaged, which eventually leads to an abnormal sound during acceleration.

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.

Gearbox problems. It could be gearbox bearing wear and reduced lubricating fluid. The gearbox is a more precise and complex component in the auto parts, there is an abnormal sound when driving, and the sound disappears when the clutch pedal is pressed, then it is very likely that the parts of the transmission have a problem, the gear gear in the gearbox is generally empty on the shaft, and the shaft is equipped with a needle roller bearing, when the rolling bearing of a certain gear is broken, the meshing will be affected, and there will be a sound because there is no radial positioning.

Precautions for car accelerationIf you are driving an automatic transmission car and you need to increase your speed, you may need to take a certain approach by not just stepping on the accelerator. For example, if it is a car with automatic hands, you can switch to manual transmission mode, then put a low gear, and then step on the accelerator, and the speed increase will be very fast. Even if there is no manual mode, you can switch to S or L mode.

In this way, if you step on the accelerator again, the speed of the car will increase, and it will be very fast.

The car engine can burst out the strongest torque within a certain speed range, so for manual transmission models, when you step on the accelerator deeply but do not feel that the vehicle has a significant acceleration, you may wish to try to downshift and speed up, with the help of low gear, high torque to achieve the fastest acceleration. It should be noted that the fuel should be replenished at the moment of downshifting, so that the operation power delivery will be smoother and more effective.

Causes: 1. The sensor is damaged, the contact is poor or the signal is interrupted; 2. Poor engine maintenance; 3. The quality of fuel and oil is not good; 4. The combustion of the mixture is insufficient; 5. Spark plug failure, ignition coil failure; 6. The fuel pump is faulty and the oil circuit is blocked; 7. The air conditioner filter is blocked.

1. Sensor problems; The sensors mentioned here include water temperature, crankshaft position, air flow, intake air temperature, oxygen sensor, etc., when these sensors are damaged, poor contact or signal interruption, the ECU of the car can not accurately obtain the engine data, at this time it will cause the engine fault light to turn on. 2. Maintenance problems; Poor engine maintenance is the most common cause of engine failure to light up. We know that the vehicle has a certain maintenance cycle, if the owner does not maintain on time, coupled with bad driving habits, then it will increase the burden of engine operation, and finally can only remind you through the fault light to care about your car 3, oil quality problems; The oil quality here includes fuel and engine oil, we know that the fuel filled by the car is generally marked, and the engine oil is also semi-synthetic and fully synthetic, the manufacturer will generally recommend the owner to use which grade of fuel, which type of engine oil, if the owner does not add as required, it will cause wear and tear of the engine in the long run, and the fault light is not to blame.

Poor combustion of the mixture; The failure of the spark plug, ignition coil, fuel pump, and oil circuit blockage of the engine will cause poor combustion of the engine mixture. Poor combustion of the mixture is caused by the problem of engine carbon deposition or knocking, and these will eventually be detected by the engine's oxygen sensor and reported to the ECU, which will naturally turn on the fault light to warn of the intake air intake problem; When the engine burns, it needs to take intake, the air filter element is very important in this process, if the air filter element of the car is not clean, it will affect the air intake of the car if it is not cleaned regularly, and it will be blocked for a long time, and if it is serious, it will cause the engine failure light to turn on. pressurization issues; Intake booster lines and turbochargers can also cause engine failure lights to illuminate.

The most common of these is turbocharger damage, while the vehicle can also experience symptoms such as oil leakage, high oil consumption, loss of power, metal noise, and blue or black smoke from the exhaust pipe. 7. Exhaust problems; Rear oxygen sensor, three-way catalytic converter, exhaust camshaft and bearing. The most common of these is a failure of the three-way catalytic converter that causes the engine failure light to illuminate.

The use of leaded gasoline, the use of leaded or silicone lubricant additives, the bump of the three-way catalytic converter, and the failure of the engine oil supply system are some of the factors that can easily cause the failure of the three-way catalytic converter. anti-theft system; If the car's electronic anti-theft system fails.