What Causes Engine Noise When Accelerating?

[HazelDella]

Engine noise when accelerating may be caused by the following reasons: 1. Deteriorated engine oil. Engine oil is known as the "blood" of a car. If the oil hasn't been changed for a long time or has deteriorated, it will increase friction between cylinder valves and guides, as well as in hydraulic lifters, resulting in abnormal noise when accelerating. 2. Faulty drive shafts. Under long-term torsional fatigue and impact forces, drive shafts are prone to bending, twisting, breaking, or wear and misalignment of spline teeth. This can cause rhythmic shaking of the car's front end accompanied by abnormal noise when accelerating within a certain speed range, with the shaking disappearing or reducing when releasing the accelerator. 3. Loose or slipping belt. A slipping belt will produce abnormal noise. Once a belt slips, the resulting friction heat will cause the belt to stretch further, worsening the slipping and creating a vicious cycle. Solution: Visit an auto repair shop to check and replace engine oil, inspect drive shafts, and adjust or replace belts.