What about the car wading? The car waded with the engine running. Why?

The rainy season is coming. Dear friends, do you know what to pay attention to when wading? Summer is a season of frequent rainstorms and showers, and short-term heavy rainfall makes many cities prone to waterlogging. Today, let's talk about some precautions for wading. Pay attention to the depth, direction and velocity of water before driving, and judge whether there are obstacles such as silt and quicksand underwater. Before wading, the distributor and high-voltage line are wrapped with plastic sheets. Before a car wades, pay attention to the route and speed of the preceding car, and then observe the depth of the accumulated water to judge whether its own car can pass. Old drivers all know a trick of driving: "Fast sand and slow water" means to explore the road ahead of time and pass at the fastest speed when walking in the sand, because if you hesitate a little, you will fall into the bunker and climb out again, which will be very troublesome. Slow water means that when we wade, we should be as slow as possible, and the slower we are, the safer we are. Wading is not an easy task for drivers of any level. Some people have been driving for a long time, but they have never waded. Generally speaking, it is easy to make mistakes according to your own experience. There are also some drivers who know that crossing the water is slow, but it is often not slow enough, which will also cause harm to vehicles and even drivers and passengers. In the case of finding out the maximum water depth, as long as the water depth does not exceed the air intake of the engine, which is generally the highest position inside the hood, that is to say, as long as the water depth does not exceed the waistline of the car body, the puddle can theoretically pass. Why do you insist on being slow again and again? Water itself has resistance. If the vehicle speed is fast, the water wave pushed by the front of the vehicle can easily exceed the waistline of the vehicle body, and it is easy to enter water, which is fatal to the engine. The purpose of slowness is to pass through the water slowly without pushing up the water wave as much as possible, and the gear must be placed in the position with the maximum torque. The manual gear is generally in the first gear. If there is an L gear automatically, it is recommended to change it directly to the L gear. If there is no L gear, it is necessary to manually integrate the first gear, so as to ensure the maximum torque to deal with the possible underwater debris such as stones, mud, branches and leaves gathered by the current. It is easy to slip. For hard roads, drive slowly into the water at low speed. When driving, keep the steering wheel stable and the throttle stable, so that the car can maintain sufficient and stable power. Pass in one breath, and try to avoid stopping, shifting gears or sharp turns in the middle. Pay special attention to the sediments on underwater roads. If you find the wheels slipping or sinking, don't slam the throttle to rush. You should drive out of the water by manpower or other vehicles without turning off the engine. Because the water pressure is far less than the exhaust pressure of the cylinder, as long as the vehicle is not turned off, the accumulated water will not flow back. The reason why too many people dare not wade is that as long as the water depth exceeds the exhaust pipe, they can't cross it, which is easy to cause the engine to stall and enter the water. Actually, this statement is wrong. Generally speaking, if the water depth exceeds the height of the exhaust pipe, the automobile chassis will be flooded in most cases, resulting in the floor soaking. So if the water depth exceeds the exhaust pipe, it can't pass. Now, we only discuss whether we can cross the river. No discussion, no floor soaking. I'm just telling you when you can wade. As long as the water depth does not exceed the air inlet of the engine, even if the engine is turned off when wading, the engine can be boldly started again, and water will not flow back into the engine through the exhaust pipe. It is wrong to say that restarting the exhaust pipe in water exceeding the water depth will damage the engine unless your intake air is lower than the exhaust pipe. But so far, I haven't seen a car whose air inlet is designed to be lower than the exhaust pipe. In case of flameout at high water level, immediately turn off the ignition switch, do not try to start the engine again, move the vehicle to a safe place, raise the vehicle as high as possible, and make the water entering the exhaust pipe flow out. After the inspection, clean the electrical connection parts in the engine compartment with compressed air to prevent the accumulated water from corroding the electrical connection parts. The key components that need to be removed are: fuse box, sensor plug, and body water. After cleaning, carry out a road test on the vehicle to ensure that the vehicle is qualified.