The way to judge whether the car muffler is broken is: if the sound of the engine becomes louder, it indicates that the car muffler is broken. The symptoms of the damage of the car muffler include: difficult starting of the engine, weak driving, poor acceleration, unstable operation of the engine, non operation of individual cylinders, and even engine shaking. There are bubbles at the water inlet of the radiator, and sometimes water drops from the exhaust muffler. The automobile silencer is mainly used to reduce the exhaust noise of the engine and enable the high-temperature exhaust gas to be safely and effectively discharged. It is a part of the exhaust pipe. Its principle is that the automobile exhaust pipe is composed of two pipes with different lengths. Because the length difference of the two pipes is equal to half of the wavelength of the sound wave emitted by the automobile, the two rows of sound waves interfere with each other when superimposed, counteract each other and weaken the sound intensity, so as to have the effect of silencing.