Often, after the acquisition of Chevrolet Niva in the secondary market and the first replacement of oil, owners notice the appearance of a knock under the valve engine immediately after launch. Most often, this happens when the half-synthetic oil is replaced with synthetic oil. A step is not a direct indication of the malfunction of the engine. The synthetic oil has a lower viscosity, so it shall be slowed down with the right pressure to hydrocompensate capacitors. When the necessary pressure is created in the area of hydrocompensators, the knock disappears. If the knock does not disappear after soaking, possibly hydrocompensators are worn out and the use of half-synthetic oil should be returned.