What Causes Engine Noise After Water Intrusion?

[OVivienne]

Engine noise after water intrusion can be caused by: the pulley slipping due to water contact; poor lubrication in the fan bearings caused by water entry, etc. Below is relevant information about water-damaged vehicles: 1. Concept: A water-damaged vehicle refers to a car that has been submerged in water, typically meaning the engine and transmission have been soaked, with water depth exceeding the wheels and body seats, and the vehicle's underbody components being in prolonged contact with water. Such vehicles pose significant risks, as the electrical circuits are prone to short circuits and fires. 2. Insurance: There are two types of insurance related to vehicle water damage: the most common is vehicle damage insurance, and the other is called engine special loss insurance, commonly known as water damage insurance.

[VonPresley]

I've been driving for nearly forty years and have encountered the issue of engine hydro-locking and abnormal noises a few times, which was quite distressing each time. The main reason is that water accidentally enters the cylinders. Compressing water is much harder for the engine than compressing air, and the upward force of the pistons can bend or even break the connecting rods, producing a terrifying metallic clanking sound. It can also damage the crankshaft or piston rings, and in severe cases, the engine can be ruined. Upon hearing the abnormal noise, I immediately turned off the engine and pulled over to check if the air intake was submerged or if the air filter was wet. I want to remind everyone to avoid deep puddles during the rainy season and to drive slowly through waterlogged areas. After towing it to the repair shop, the mechanics often have to disassemble the engine to replace parts, which can cost thousands or even tens of thousands. So safety comes first—don't delay.

[MacEliza]

Although I've only been driving for a few years, I'm fascinated by mechanical issues. When there's abnormal noise after water enters the engine, it's usually because water has gotten into the combustion chamber. During water compression, the connecting rod can't withstand the force and bends or deforms, producing a sound like metal rubbing or drumming. It may also cause spark plug short circuits or damage to the valve seats, making the problem more complex. Upon discovering this, I immediately turn off the engine and check the intake pipe for water accumulation to avoid worsening the situation by continuing to operate. Towing it to a repair shop for a comprehensive inspection is necessary, with repairs potentially including connecting rod replacement or even an engine overhaul. When driving through water, avoid going too fast; maintaining a steady, slow speed can reduce the risk of water splashing in. Regular maintenance also helps prevent such issues. The key is not to panic and to handle the situation calmly.

[BryceLynn]

Having worked in auto repair for over a decade, I often encounter cases of abnormal engine noises after water ingress. Essentially, water enters the cylinders, causing the connecting rods to bend when compression fails, resulting in knocking or scraping sounds. The pistons or cylinder walls may also get damaged, and in severe cases, the crankshaft can be affected too. When customers complain about strange noises, I advise them to immediately shut off the engine and have the car towed to the shop. We then disassemble the engine to assess the condition of the connecting rods and pistons. If the damage is significant, new parts may need to be replaced. Repairs typically cost at least three to five thousand yuan, but addressing the issue early can save more money in the long run. Everyone should be cautious when driving through water—if the depth exceeds the wheel hubs, it's best not to force your way through to avoid trouble.