What is the reason why there is a sniffing sound when stepping on the gas pedal?

What is the reason why there is a sniffing sound when stepping on the gas pedal? Air leakage in the intake system, excessive valve clearance, dirty gearbox oil and aging belt will all make refueling sound. The following is the introduction and solution of abnormal noise during refueling: Cause: Air leakage in the intake system is the most common fault problem. When there is a crack in the air intake system of the vehicle, the high-speed airflow will be discharged from the crack, resulting in a hissing or whistle sound. Influence: If the intake pipe is seriously damaged, it will greatly affect the power output of the vehicle and increase fuel consumption. Solution: When abnormal noise occurs, it is best to go to the repair shop as soon as possible to check whether the intake manifold is leaking. @20 19