What Causes a Spongy Brake Pedal?
2 Answers
The causes of a spongy brake pedal generally include the following. Here are the specific reasons: 1. Mixing brake fluids of different brands, which reduces braking performance, or continuing to use brake fluid beyond the manufacturer's recommended replacement period, causing the brake fluid to deteriorate and its boiling point to drop. 2. Air in the brake fluid. 3. External rubber damage or bulging of the brake hose leading to pressure loss. 4. Leakage or poor sealing of the master cylinder and wheel cylinders. 5. Additionally, check whether the brake pads are original equipment. As a critical component for safe driving, the braking system should be given special attention by every driver. Before each drive, test the condition of the brake pedal. Before starting the engine, the brake pedal should feel very firm; after the engine is running normally, the brake pedal may sink slightly, which is normal.
I've been driving for almost twenty years and have encountered the issue of soft brakes several times. The most common cause is air getting into the brake system, making the pedal feel spongy when pressed. Low or aged brake fluid can also cause this, as it absorbs moisture and lowers the boiling point. Another factor is excessive wear on brake pads, which directly reduces braking force. I remember last year my car almost had an accident because of this, but luckily I went to the repair shop in time to bleed the air and replace the fluid. Now I check the brake fluid level myself every month to ensure it's not low, change the fluid every two years, and regularly inspect the brake pad thickness. Proper maintenance is the only way to drive with real peace of mind—don't skimp on these small expenses!
