Will the throttle ring after stopping and turning off the engine?

Mine is a famous 1.8 self-esteem, produced on 20 15. 10, and picked up the car in 65438+February. Maybe I didn't notice it before. The phenomenon is this:

Turn off the engine after driving, and the front of the car will make a noise. Later, I opened the hood and listened carefully. It was as intermittent as the sound of magnet attraction, and there would be 2-3 times of attraction and release every time I turned off the engine.

Then I went to 4S for car inspection today, and the car inspector said it was normal, saying that the throttle was off, but other cars didn't hear it. Next time, find a famous map to see if other cars have this sound, and I don't know if he is right.