At what water level should a car not be driven when submerged?
4 Answers
A car should not be driven when water reaches the intake level. Below are the specific impacts of water entering the vehicle: Rust and corrosion of the vehicle: Once water enters the floor, it can cause corrosion to the floor and metal components, particularly accelerating rust on metal parts, leading to vehicle malfunctions and increasing risks for passengers. Vehicle wiring short circuits: There are numerous wiring lines under the vehicle's floor. If water enters, these lines may short-circuit, affecting normal vehicle operation and potentially damaging the onboard computer due to electrical faults. Vehicle odors: If the vehicle floor gets wet and is not promptly treated, the damp floor can easily mold and deteriorate, producing unpleasant odors inside the car.
I think a car shouldn't be driven if the water level reaches the door sill. Based on my years of driving experience, once the water exceeds the bottom of the door sill (about 15 cm deep), it can easily enter the engine compartment or exhaust system. Last year during heavy rain, a friend's car was submerged to that height, and he forced it to drive, resulting in water entering the engine and costing tens of thousands to repair. Key components like the air filter are located above the chassis, and water ingress can cause the engine to stall or even be completely ruined. Electrical system short circuits are also common, with dashboard lights flickering erratically. Therefore, it's best to stop driving if the water level rises above ankle height and either find an alternate route or wait for rescue. Driving through floodwater is highly risky, as the car body may float, making it hard to control the direction. For safety, check the underbody protection before the rainy season and avoid deep water areas. Remember, never start a water-submerged car immediately—have it towed and inspected by professionals first.
Driving my small car during the rainy season becomes dangerous when the water level reaches half the height of the tires. Generally, the distance from the ground to the center of the wheel is about 10 centimeters or so. If water rises above that point, it can seep into the exhaust system or chassis, leading to corrosion or short circuits. Last time I drove in heavy rain, the water reached the bottom edge of the door, and I felt the car starting to float, so I immediately slowed down and stopped. Electronic components are prone to moisture damage, causing issues with lights and audio. Even worse, water entering the cabin can soak the carpets, leading to mold and unpleasant odors. It's advisable to avoid water deeper than 15 centimeters. If you must pass through, drive slowly in a straight line to avoid creating waves. Observe whether other vehicles are passing through safely—safety first. If unsure about flood levels, use a map app on your phone for assistance.
Do not drive through water levels that submerge the air intake, as it is a critical point. The air filter is located near the door sill. If water reaches there, it can enter the engine cylinders and cause hydrolock, damaging the pistons. Risks are also high when water submerges more than half of the tires, as electrical circuits in low positions are prone to short circuits. Flood depths exceeding 20 cm may cause the vehicle to float and lose control. Do not start the car after flooding, as repairs are troublesome and costly. Different vehicles have varying intake heights, with sedans being more vulnerable than SUVs. Regular maintenance, including checking exhaust systems for rust, can help prevent flood damage.
