What are the symptoms of incomplete brake air bleeding?
2 Answers
The symptoms of incomplete brake air bleeding are: 1. After starting the vehicle, when forcefully pressing the brake pedal, the pedal goes all the way to the floor; 2. After starting the vehicle, the first press of the brake pedal feels very low, but becomes normal after a few presses. If the brake pedal is released for a few minutes and then pressed again, the first press feels very low again, but returns to normal after a few presses. Brake fluid is incompressible, while air is compressible. If there is air in the brake system's hydraulic circuit, the feeling when pressing the brake pedal is completely different, giving a sensation of gas compression and rebound. Air in the hydraulic circuit can affect the transmission of braking force, weakening the braking power. The method to bleed air is through bleed ports at the end of each wheel's brake line, but the operation is relatively complex and should be performed at a professional repair shop.
After repairing cars for so many years, I've noticed that the issue of incomplete brake air bleeding has quite obvious symptoms. The most noticeable one is the brake pedal becoming soft and spongy, feeling hollow when pressed with little feedback, and the travel distance becomes excessively long. Sometimes you have to press it very deep to engage the brakes. The braking efficiency is significantly reduced, stopping distance noticeably increases, and driving feels particularly unsafe, especially during emergency braking at high speeds where the risk of rear-end collision or losing control is high. Another symptom is a clicking sound or slight vibration when braking, as if there are air bubbles being compressed in the system. I advise fellow drivers not to ignore this issue. Promptly visit a professional repair shop to re-bleed the brakes, check the brake fluid level and pipeline seals. Safe driving is a matter of life and death.
