Nc250 can't get down at idle speed.

In addition to using high-grade qualified fuel, it is necessary to thoroughly clean the oil circuit, including the fuel nozzle, throttle valve and fuel tank. It may be that the quality of the oil you added is not up to standard, and there is too much gum, which blocks the oil circuit and causes poor oil supply. As for the flameout when the car is idling, the solution to this problem is simple: just clean the idling motor.