What Causes the Loud Engine Noise in the Mazda3 Axela?

[NovaAnn]

Mazda3 Axela's loud engine noise is due to its use of a direct injection engine and an added heating system. The specific reasons are as follows: Use of a Direct Injection Engine: The Mazda3 Axela uses a direct injection engine, which naturally produces louder noise during cold starts. This is a normal phenomenon. The loud noise during cold starts is a common characteristic of direct injection engines. The increased noise is intended to quickly bring the engine back to its working state and ensure thorough internal lubrication. All vehicles increase idle speed under the control of the onboard computer during cold starts to achieve rapid warming up, resulting in louder startup noise. Mazda3 Axela's Added Heating System: Skyactiv models, including the Mazda3 Axela, feature an extended exhaust system and an independent heating system specifically added to suppress cold engine detonation. This system generates relatively loud noise during operation, making the noise during the warm-up phase louder than that of ordinary vehicles.