The deceleration of Lexus NX is the increase of idle speed. What is the increase of nasal sound?

The reason for the sudden increase of idle speed when the car slows down is that too much carbon deposited in the idle valve will affect idle speed and then damage the idle motor. Check whether the air intake system leaks, and check the use of all parts of the ignition system. Idle state refers to the working state when the engine is idling. When the engine is running, if the accelerator pedal is completely released, the engine will be at idle speed. When adjusting the idle speed, the speed should not be high and low, otherwise it will cause early wear and tear to the engine, so it is best to adjust it in the automobile maintenance department.