What are the effects of a sedan passing through deep water without stalling?

[VonGeorge]

Theoretically, as long as water does not submerge the air intake, it will not affect the engine. However, there are too many unpredictable factors, such as waves caused by passing vehicles that might splash into the air intake, or unknown underwater conditions like potholes, which can affect the vehicle's passability. If the car does not stall while driving through deep water, it indicates that the air intake did not take in water. Below are precautions for driving in rainy weather: 1. Slow down: Regardless of road width or condition, always drive slowly in the rain, constantly observing the distance between vehicles ahead and behind, and be mentally prepared to take emergency measures. Visibility is low in the rain, and the vehicle's emergency performance, such as braking distance, is reduced, so slow down in advance to allow enough time and space to handle situations safely. 2. Maintain distance: Driving in the rain obstructs visibility, so it's important to keep a safe distance from other vehicles, constantly observing the distance ahead and behind, and increasing the following distance. Stay especially far away from large vehicles, as they can block your view, and the water they splash can interfere with your driving. Additionally, large vehicles may pass through water that smaller vehicles cannot. 3. Use fog lights: Make full use of fog lights to enhance driving safety in the rain. Turn on hazard warning lights when necessary to alert vehicles behind you to your movements. 4. Do not restart if stalled: In heavy rain or storms, some areas may flood quickly. If you must drive through water, do so at a steady speed in a low gear. If the vehicle stalls during the process, do not attempt to restart it immediately, as this could severely damage the engine. Instead, contact a professional repair shop promptly. Only restart the vehicle after a mechanic has inspected it on-site and confirmed there are no issues.

[LeValerie]

Last time I drove my sedan through deep water without stalling, I thought everything was fine. But a week later, strange noises started coming from the chassis. At the repair shop, they found water accumulation in the exhaust pipe causing rust, and the catalytic converter was also damaged. Although the engine didn't take in water, the water pressure deformed the chassis guard plate, and the brake discs rusted from water contact, leading to longer braking distances. The most troublesome part was that sand and mud got into the wheel bearings, causing a humming noise while driving. The mechanic said that after driving through water, you should immediately check the chassis seals and exhaust system. Otherwise, these hidden damages will gradually show up and end up costing more than an engine stall.

[DeMargaret]

As a mechanic frequently dealing with flood-damaged vehicles, I've noticed that the hazards of water-submerged cars left running are often overlooked. Electrical system connectors are prone to oxidation and short circuits, particularly with oxygen sensors and ABS wiring harnesses - warning lights may inexplicably illuminate after water exposure. Water ingress into chassis ball joints and tie rod rubber boots accelerates aging, while transmission breather holes positioned too low may allow water contamination of fluids. Although the vehicle may be drivable immediately, I recommend promptly checking differential and transfer case fluid conditions, as water contamination causes abnormal metal component wear. A full vehicle electrical inspection is advisable to prevent potential fire risks.

[LeGenevieve]

Last year during a heavy rainstorm, I drove through a waterlogged section without stalling, and I secretly rejoiced at having dodged a bullet. But the next day, I noticed a musty smell inside the car. Upon removing the carpet, I found the sound insulation foam soaked with water, and the seat brackets had rusted. Even more annoying was the strange noise from the air conditioning blower after it got waterlogged, costing over 800 yuan to fix. Deep water pressure can deform door seals, and it’s also common for sunroof drain pipes to backflow. Now I’ve learned my lesson—after driving through water, I always check under the carpet and the air filter, as these are the places where hidden water can do the most damage to the car.

[DeJames]

Having modified cars for ten years, I fear water wading the most. Even if the engine is fine, the impact of water waves can cause moisture condensation inside the exhaust pipe, leading to electrochemical corrosion—the muffler can rust through in just three months. Cars with modified suspensions need extra caution, as water can cause the shock absorber oil seals to fail and leak. A friend's performance car had its differential lock seize after wading through water; upon disassembly, it was found that water entered through the vent hole, causing the lubricant to emulsify. It's advisable to promptly clean off mud and sand from the undercarriage and thoroughly check the sealing of aftermarket parts, especially around the intake duct.

[AubreeMarie]

Once helped a friend deal with a waterlogged car. On the surface, it seemed lucky that the engine didn't stall, but upon disassembly, we found the transmission radiator gaps clogged with aquatic weeds. The blocked cooling fins caused the oil temperature to skyrocket, turning the steel belt blue. The key issue was the torn steering gear dust boot letting water in, making the steering heavier and creaky. The mechanic mentioned that the crankcase vent tube at the bottom of the intake manifold might have siphoned water, contaminating the engine oil. Now, whenever encountering a flood-damaged car, we always check the cooling system and oil condition—these hidden damages are harder to detect than engine failures.