After changing the engine oil, the engine noise increases and the acceleration is weak. What's the matter? Take a look at these seven culprits!

Have you had that experience too?

After the maintenance of the car, the performance of the engine has changed significantly. Especially when it starts, the noise becomes louder and the power performance weakens. Whose pot is this? Is there a problem with the new oil?

1. Excessive oil

The liquid level of the oil is strictly controlled. Pull out the oil dipstick and you can see that the ruler is marked with the lowest scale and the highest scale. It is best not to exceed this scale line when adding oil. The best state is that there is only a difference between the two. About one centimeter, too high or too low will hurt the car.

It is easier to understand if the oil is added less, which will easily lead to insufficient lubrication and engine wear. Adding more oil is also very harmful, which produces greater resistance to the rotation of the crankshaft, which affects the power output and increases fuel consumption. The amount of oil entering the combustion chamber is greatly increased, which increases the carbon deposit in the combustion chamber, increases the resistance of the piston movement, and reduces the engine power. At the same time, it will also cause changes in the air-fuel ratio of the combustion chamber, increase the probability of knocking, and increase the noise.

2. Serious carbon deposition

Under normal circumstances, people pay more attention to the selection and replacement of oil for car maintenance, but other car owners will not pay too much attention to it. It is precisely because of this that the engine can easily accumulate a large amount of carbon deposits.

Carbon deposits accumulate in fuel injectors, spark plugs, throttles, combustion chambers, etc. During the fuel combustion process, part of the fuel is adsorbed by the carbon deposits. After adsorption, the carbon deposits continue to accumulate, resulting in more and more carbon deposits under a vicious circle. Therefore, the fuel sprayed from the fuel pump head will be absorbed by carbon deposits, and failure to supply fuel in time will cause weak acceleration and increased noise.

3. Oil viscosity problem

Different grades of engine oil have different characteristics, and their low-temperature startability and high-temperature anti-wear and adhesion also have different performances. The viscosity of the oil is inversely proportional to the temperature. When the engine is cold, the oil viscosity is higher. If the selected oil is thicker, it will add additional losses to the starter motor and battery.

However, if the oil is too thin, it is difficult to form a sufficient protective film under high temperature work, which will cause insufficient lubrication and cause increased wear of the parts. If the vehicle manual recommends 5W-30, and the owner uses 5W-40 to make the engine noise louder, then the owner needs to pay attention. It is recommended that the oil should be the label recommend in the vehicle manual.

4. Oil mixing

This situation is also more common. The additive formula of each engine oil is also different. If you mix it at will, it is likely to cause chemical reactions between the additives, reduce the lubrication effect, cause precipitation and stratification, and reduce the cleaning performance, resulting in oil failure.

This situation can easily cause wear and tear on the engine and increase the sound. It is recommended that riders should not mix oil and try to use the same brand of oil. In case of special circumstances to replace different brands of oil, it is best to use the same grade oil after cleaning the engine.

5. Fake oil

Lubricating oil in the manufacturing process, the use of additives, base oil composition and other aspects are different, so there are so many types of oil on the market. However, the production of fake engine oil will not consider these complex formulas, so the performance of anti-wear, cleaning, and lubrication protection is very poor, which can easily lead to excessive engine pressure, which will increase wear and noise.

6. Low temperature cold start

During a cold start in winter, strong noise may be felt. Because most of the oil flows back to the oil pan in a cold car, the internal components of the engine lack lubrication at this time, and the engine temperature will become lower when the cold car starts, and the lubrication performance of the oil will not reach the best state, plus the engine warm-up The reason for the speed will cause the noise to be too loud, but the noise speed will drop again after the hot car. This is normal.

If the car does not return to normal after warming up, it is recommended that everyone check it. In addition, it is best to use oil with better low temperature fluidity in winter, which can effectively avoid such situations.

7. Engine failure problem

In addition to the increase in engine noise caused by the above factors, it is also necessary to pay attention to other factors such as whether there are parts failures in the engine compartment, whether the engine lacks cylinders, and whether the engine's intake and exhaust pipes are leaking.

There are many factors that cause the engine noise to become larger, so don't take it lightly and find the root cause of the fault in time.