When the car is idling, it is said that it will be released after stepping on the accelerator for 4000 rpm, and then the speed needle will stop when it falls back to1000 ~1200, and then slowly.

No, you are hurting the engine and wasting oil. There is no need to do so. If the throttle is not dirty (reducing the formation of carbon deposits), we must first understand the causes of carbon deposits. At present, the EFI engine injects oil into the cylinder first and then ignites it every time it works. When the owner turns off the engine, there is always gasoline ejected from the cylinder and burned at the end of ignition. After the gasoline remaining in the cylinder, valve and combustion chamber volatilizes, the residual gum and paraffin wax accumulate thicker and thicker, and harden after repeated heating to form carbon deposits.