Engine refueling is not smooth, how to tell whether it is a spark plug problem or a dirty throttle by sound?

If the spark plug has too much carbon deposit or the gap is too large and aging, it will feel that the throttle is boring when the car is in gear, as if it does not give oil. Yes, by the way, check the cylinder pipeline and distributor and change the gasoline filter. Too high or unstable idle speed is a problem with the throttle. I am also a public opinion. Some time ago, you encountered such a problem. I thought it was saving energy. I just got a new one, and it's useless. Later, I heard a friend say that the spark plug should be removed. At first glance, it turned out that there was too much carbon deposition. After I replaced it with a new one, there was no problem at all. I really regret changing the throttle and spending more than 200 yuan. Hmm. How interesting