What's the rumble of the car chimney?

What's the rumble of the car chimney? The following are the reasons for the abnormal sound of the car chimney: 1. Air leakage in exhaust pipe: When air leaks into the exhaust pipe, the vehicle will accelerate and the exhaust speed will increase, and then the vehicle will have a loud roar. 2. Dirty throttle: When the car accelerates, the load of the engine begins to increase. At this time, it is necessary to increase the throttle opening and increase the fuel quantity. If the throttle opening is not opened to the optimal position due to dirty blockage, it will cause poor engine mixing ratio and make noise when accelerating. In addition to the roar, there is often a buzz when the engine accelerates. The possible cause of this sound is: 1, gearbox problem. The hum generated during acceleration is not necessarily from the engine, but may also be caused by the wear of gearbox bearings, the decrease of lubricating fluid and the friction. 2. Engine problems. If it is indeed the hum of the engine, observe whether the speed is high. If the speed increases and the vehicle speed increases slowly during acceleration, this situation is generally that the clutch slips and the clutch kit needs to be replaced. @20 19