Link 0 1 Start loudly. Is it normal?

This is normal. It takes a process to establish the oil pressure of the engine cooler, so the lubrication effect is not good and the noise is high. In addition, after the air-to-air shunt is started, the engine quickly reaches the normal working temperature, the idle speed becomes higher and the noise becomes louder. Then with the decrease of idle speed, the noise gradually becomes smaller and disappears. 1. Because of the carbon deposit in the engine, the used engine oil is getting thinner and thinner, and there will be more carbon deposit. When the oil becomes thinner, the oil will easily escape, the carbon will easily accumulate, and the knife will lose a lot of power. If the engine oil is replaced with new oil, the engine cannot adapt to the viscosity of the oil, the number of revolutions becomes higher, and the engine noise may become louder. Solution: Go to the 4S shop regularly to clean the air intake system of the car, which can most effectively reduce the formation of carbon. It's about 30 thousand kilometers. You can clean the air intake system of the car. 2. Because the oil does not meet the benchmark, or it is added too much. Too much oil will cause unnecessary resistance to the rotation of crankshaft, affect power output and increase fuel consumption. When the carbon deposit in the cylinder is in a red-hot state, it is easy to cause early combustion and aggravate the wear of the cylinder and piston. The increase of carbon deposit will also affect the quality of engine oil. In short, if there is too much oil, the mixing resistance of crank and connecting rod will increase and the noise will also increase. Solution: Change the oil regularly and appropriately (generally slightly lower than the upper limit of the oil standard), and clean or replace the filter element of the oil filter regularly.