Why Is There a Popping Sound When Braking?
2 Answers
It's the sound of the hydraulic pump, indicating that the brakes are functioning normally. Below is relevant information about braking: 1. Definition: Braking, also known as deceleration, refers to the action of stopping or reducing the speed of moving locomotives, vehicles, other transport tools, or machinery. The general principle of braking involves fixing a wheel or disc on the machine's high-speed shaft and installing corresponding brake pads, bands, or discs on the machine base to generate braking torque under external force. The braking device is a mechanical deceleration device that can slow down the vehicle's speed, also known as a retarder. 2. Classification: Braking can be divided into emergency braking and regular braking. During emergency braking, be aware of the potential hazard of rear-end collisions from following vehicles.
In the past, I often encountered a 'puffing' sound when stepping on the brakes, especially when driving an old car on mountainous roads with frequent uphill braking. At first, the sound was not loud, so I didn’t pay much attention, but later, during an emergency brake, I almost rear-ended another car and realized the severity. After researching and consulting a mechanic, I learned that this is mostly caused by air entering the brake system—such as aging pipes leaking air or incomplete bubble removal when replacing brake fluid during maintenance. When braking, the bubbles compress in the hydraulic lines, producing the sound. Additionally, a loose seal in the brake booster pump might draw in air, creating a 'puffing' noise that sounds like a small pump working. In severe cases, air can make the brakes feel soft or fail, which is especially dangerous at high speeds. My advice is not to delay once you hear the sound—visit a professional repair shop as soon as possible for a system bleed and inspection. The cost is low but ensures safety. During regular maintenance, pay attention to brake fluid levels and replace it periodically to avoid moisture buildup, especially after the rainy season. Safe driving starts with the details.
