Why does the engine make a humming noise at idle that disappears when accelerating?

[Jayce]

Idle humming noise is caused by insufficient engine oil, and the disappearance when accelerating is due to the engine burning oil. Always check the oil level. Here are the reasons for idle humming noise and corresponding solutions: 1. Loose components in the engine compartment causing resonance and abnormal noise. Solution: Identify and tighten the loose component to resolve the issue. 2. Humming noise during high-speed driving, caused by insufficient lubrication or abnormal wear in wheel bearings. Solution: Determine which bearing is making noise and replace it to solve the problem. 3. Humming noise when suddenly accelerating while driving. This is usually the sound of the turbocharger working. If this is the case, no repair is needed as this is a normal sound, though the volume may vary.