To what extent does water submersion affect a car?
3 Answers
Water reaching the engine can cause stalling and malfunctions. Below is relevant information about cars being submerged in water: 1. Handling: If a car is submerged while stationary, the engine typically won't be damaged, and compensation can be claimed if comprehensive insurance is purchased. However, if you impulsively attempt to start and drive the car out of the flooded area, causing engine damage, even with water ingress coverage, the insurance won't compensate. Another scenario is when the engine stalls and malfunctions during water wading. If you have water ingress coverage, also known as special engine loss insurance, you can file a claim with the insurance company. Conversely, if you only have comprehensive insurance without water ingress coverage, only non-engine parts will be compensated. Of course, if engine damage results from restarting the engine in water, even with water ingress coverage, the insurance company won't compensate. 2. Special cases: Despite all precautions, there's one unexpected situation you might encounter. This involves a potential 'reckless teammate' in your car called 'engine auto start-stop'. If engine water damage occurs due to this feature during water wading, even with water ingress coverage, the insurance company will deny the claim.
I often deal with flood-damaged vehicles, and the water level height is the key factor determining the extent of damage. If the water only reaches the bottom of the wheels, about 30 cm deep, there might be little harm, possibly just rust on the chassis or water getting into the brake system. However, once the water level rises above the exhaust pipe outlet, approximately 40 cm or more, starting the car can cause water to enter the exhaust pipe, damaging internal engine components such as stuck pistons or bent connecting rods, which are costly and labor-intensive to repair. Even worse is when water reaches the middle of the car body, such as flooding the door frame, allowing water to invade the cabin, causing short circuits in the electronic systems, and potentially disabling the air conditioning and audio systems, with interior upholstery becoming moldy and deteriorating. When the depth exceeds 60 cm, the risk of water entering the engine increases significantly, and if the electrical circuits are completely damaged, the car may be beyond repair and only fit for scrapping. Therefore, it's best to avoid waterlogged roads. If your car gets flooded during heavy rain, do not attempt to start it—instead, have it towed to a repair shop for a thorough inspection immediately.
I’ve also driven through heavy rain myself, and the water level directly affects the safety of the car. A small puddle reaching halfway up the wheel hub has minimal impact on a regular sedan—at most, the chassis might get a bit damp, but the chassis armor can offer some protection. If the water reaches the height of the exhaust pipe, never attempt to start the engine, as sucking in water could destroy the engine, leading to thousands in repairs. When water rises to the door sills, the interior may leak, soaking the seats and carpets, which can lead to mold and bacteria growth, posing health risks. In deeper water, like submerging the dashboard, the car is essentially totaled, with wiring and control modules ruined beyond affordable repair. Always check weather forecasts and avoid driving through floods. If the engine stalls, prioritize safety and wait for rescue.
