What causes the loud engine noise when driving the Song Plus?

[MargaretDella]

Song Plus may produce loud engine noise due to poor sound insulation, insufficient coolant, or the engine not adapting to the oil viscosity. Below are detailed explanations and solutions: Engine adaptation issue: After prolonged driving, engine oil gradually thins and carbon deposits accumulate. When new oil is replaced, the engine may not immediately adapt to the oil viscosity, potentially causing higher RPMs and consequently louder engine noise. This noise may decrease after oil replacement or with extended usage. Poor sound insulation: Loud noise may result from inadequate engine sound insulation. Inspect the vehicle's sealing strips - if they show signs of aging, replacement is necessary. Insufficient coolant: Coolant levels can drop in low temperatures, leading to increased engine noise. Adding coolant can resolve this issue.