Why Does a Car Engine Sound Louder in Winter?
2 Answers
Winter car engine noise may be caused by substandard engine oil, unsuitable oil viscosity, carbon buildup, and other reasons. Below is an analysis of the reasons for increased engine noise in winter: 1. Substandard engine oil or excessive oil level: When there is too much oil in the engine, it creates unnecessary resistance to the crankshaft's rotation, affecting power output and increasing fuel consumption. 2. Unsuitable oil viscosity: Different grades of engine oil have varying characteristics, including low-temperature startup performance and high-temperature anti-wear and adhesion properties. However, if the oil is too thin, it may fail to form a sufficient protective film under high-temperature conditions, leading to insufficient lubrication and increased component wear. 3. Carbon buildup: As old engine oil becomes thinner over time, carbon deposits accumulate more easily. Thinner oil can lead to oil seepage, increasing carbon buildup and reducing engine power. When new oil is added, the engine may struggle to adapt to the new oil's viscosity, potentially causing higher RPMs and resulting in louder engine noise.
Having driven sedans for over a decade, I've noticed the engine hums noticeably louder every winter, which is quite common. There are several main reasons for this: in cold weather, engine oil thickens, reducing lubrication effectiveness. This increases friction between moving parts inside the engine, such as pistons and connecting rods, amplifying noise. Additionally, metal components contract in the cold, enlarging gaps and causing unusual sounds during operation. Furthermore, batteries discharge more slowly in low temperatures, requiring greater current during startup, which makes the engine sound louder. Warming up the car for a few minutes before driving can help alleviate this, as can using 0W or 5W low-temperature engine oil. While this condition isn't typically cause for long-term concern, if you hear knocking sounds or experience significantly increased vibration, it's important to get it checked promptly to prevent wear on engine components that could affect longevity.
