Can a Car Start If the Exhaust Pipe Is Flooded?
2 Answers
Water entering the car's exhaust pipe does not affect the normal operation of the engine, and the car can still start. When driving in the rain or going to a car wash, it's important to prevent water from entering the muffler, as this can lead to rust and affect the exhaust pipe's functionality. If water accidentally enters the muffler, immediately start the engine to warm up the car and try to expel the accumulated water from the muffler. If the water depth exceeds half of the wheel height, it's best not to force your way through. When driving through flooded areas, the vehicle should be in low gear with steady throttle to pass smoothly. Driving at high speed can cause water splashes from the front wheels, bumper, or front grille to wet high-voltage lines in the engine compartment, leading to stalling. Alternatively, water may surge into the air intake, reach the air filter, and eventually enter the engine, causing it to stall. During actual driving, as long as the engine does not stall, the exhaust pipe continuously emits exhaust gases, which prevent water from entering the exhaust pipe. Therefore, the main concern during water wading is not the exhaust pipe but the air intake. The real reason for a car stalling after wading through water: The engine operates by burning a mixture of fuel and air in the cylinders to drive the vehicle. However, if water mixes into the fuel-air mixture, the vehicle will stall because it "chokes on water," which is the primary cause.
Last time my colleague parked his car in a flooded area during a heavy rainstorm, and the exhaust pipe was completely submerged in water. In a hurry to get home, he forced the ignition to start the car. As a result, after driving only about ten meters, the engine suddenly made a loud clanking noise and completely stalled. When towed to the repair shop and disassembled, it was found that water had backflowed from the exhaust pipe into the engine, bending two connecting rods, and the repair cost alone was over thirty thousand yuan. In fact, when water submerges the exhaust pipe, the insufficient exhaust pressure during startup can suck the water inside. When the piston compresses the water, liquid water, unlike air, cannot be compressed, and forcing it can damage core components. Now, when encountering such situations, I directly call for a rescue tow truck and never take the risk of igniting the engine.
