What Causes the Rustling Sound After a Car Drives Through Water?
3 Answers
There are many reasons for the sound after a car drives through water, mainly including water on the brake pads, foreign objects stuck between the brake pads and calipers, water ingestion in the exhaust pipe, or foreign objects lodged in the chassis. Below is an introduction to the relevant content: 1. Water on the brake pads: If the car drives through shallow water and water splashes onto the brake pads, a squealing sound when braking is a normal phenomenon. This situation only requires normal driving until the water on the brake pads wears off. 2. Foreign objects on the brake pads: If the car drives through deep water, foreign objects such as plastic bags, paper scraps, or mud stuck on the brake pads can also cause noise when braking. In this case, the brake pads should be cleaned. 3. Water ingestion in the exhaust pipe: If the car drives through deep water and water enters the engine through the exhaust pipe, it can prevent the normal combustion of fuel and the air-fuel mixture in the engine, also resulting in noise.
I've encountered several instances of a rustling sound after driving through water, and I've summarized the main causes as follows: The most common issue is rust forming on the brake discs due to water ingress, with sand getting stuck between the brake pads and discs, causing friction noise when the wheels rotate. Sometimes, the sound disappears after driving for a few more minutes. Another cause is water entering the bearings, leading to lubrication failure, which results in a continuous rustling sound that doesn't vary with speed. In such cases, the wheel hub bearings must be inspected. Water entering the exhaust pipe is more noticeable, especially during cold starts when the exhaust blows out water, producing a sound similar to blowing bubbles through a straw. The belt system should not be overlooked either, as water can wet the engine belt, causing it to slip and produce a squeaking noise. It's advisable to lightly press the brakes a few times after driving through water to expel any moisture. If the sound persists after a few days, it's best to promptly visit a repair shop for disassembly and inspection.
After the car went through a deep water area last time, there was a rustling noise. My mechanic friend checked it and found it was an issue with the brake system. He said it’s quite common for sand particles to get stuck in the brake disc shield—water and mud splash in together, making it sound like sandpaper grinding against metal when driving. Water entering the wheel hub bearing can also cause noise, and a hot wheel hub to the touch is a telltale sign. Water accumulation inside the exhaust pipe is easier to identify, as the sound changes when accelerating. The sizzling sound of a wet engine belt slipping can be easily confused with the rustling noise, so careful distinction is needed. Now, I drive slowly through puddles to avoid water splashing into the engine bay. Luckily, last time it was just sand in the brake discs, and everything was fine after cleaning.
