Can I Start the Car If It's Flooded?
4 Answers
No. Theoretically, as long as the water does not submerge the air intake, the engine won't be affected. However, there are too many unpredictable factors. For example, when another car passes by, it may create waves that could splash into the air intake. Additionally, you must drive slowly through the water, and the underwater environment is unknown—even if the surface appears calm. If the car stalls while driving through water, you must not attempt to restart it. Extended Information: During heavy rain, car owners should avoid driving if possible. If driving is necessary, they should steer clear of low-lying areas, such as underpasses, overpasses, or poorly drained roads. Before setting out, plan your route and timing carefully, especially during rush hours, to avoid these low-lying areas where water can accumulate quickly, potentially leaving your car immobilized.
Never try to start the engine after your car is flooded! I personally witnessed a friend making this mistake. When his car was submerged in rainwater, he hastily attempted to start it, only to hear a dull thud from the engine—it was completely destroyed. The mechanic later explained that when water enters the cylinders, the pistons can't compress the liquid, which can bend the connecting rods or even shatter the pistons. Such damage isn't covered by insurance. Moreover, powering up the entire electronic system after it's been soaked poses a catastrophic risk of short circuits. The safest approach is to call for a tow truck and let professional technicians inspect the engine and electrical systems. Remember, the more you try to start a flooded car, the greater the damage—a costly lesson learned the hard way.
As a seasoned veteran in the auto repair industry, I've handled numerous flood-damaged vehicle cases. The key point is never to attempt starting the engine, as water ingestion can cause 'hydrolock' - at best resulting in bent piston rods, at worst causing cylinder block cracks. When submerged electrical connectors get energized, they'll oxidize and corrode, leading to endless future malfunctions. My advice: first document the damage with photos while the engine is off, then disconnect the battery negative terminal to prevent short circuits. When towing to the shop, you must remove spark plugs to drain water and take out seats/carpets for cleaning to prevent mold. This job requires patience - only strict adherence to procedures can minimize losses.
I have experience dealing with flooded cars during the rainy season: the first step is to turn off the ignition immediately. Even if the water only reaches the wheel hubs, the intake may have already sucked in water during the startup attempt. Last year, my car got flooded, but I resisted the urge to start it. After towing it away and disassembling it for inspection, we found three centimeters of water in the cylinders. The technician performed a full drainage and drying process, replaced the oil and three filters, and treated all electrical connectors with anti-rust measures. Now, it runs perfectly fine. However, another car in the same garage was started, resulting in an engine overhaul that cost over ten thousand. The key takeaway is: don’t touch the start button, don’t turn the key. Just record a video with your phone and report it to the insurance company.
