Why is the exhaust pipe of the Mazda 3 Axela so loud?

[StNathan]

The reasons for the loud exhaust pipe sound in the Mazda 3 Axela are as follows: Exhaust pipe abnormal noise: If the noise is very loud and obvious, it indicates a high possibility of exhaust pipe abnormal noise; exhaust pipe abnormal noise, that is, the fuel ignites within the exhaust system, causing the exhaust pipe pressure to suddenly increase sometimes, resulting in abnormal noise. Too small ignition advance angle: Caused by the engine's too small ignition advance angle; the switching valve is too lean, causing unsuccessful ignition in the cylinder; the mixture is too rich, causing unsuccessful ignition in the cylinder; cylinder leakage, causing too low cylinder pressure to ignite; when idling, the engine speed is low, and the exhaust system airflow speed fluctuates, if the abnormal noise is not very loud, it indicates normal operation.