What to Do When the Brake Pedal Gets Harder to Press After Engine Shutdown?
2 Answers
Methods to restore brake pedal stiffness after engine shutdown: 1. Related to pressing the brake before shutdown: A car's braking system operates at maximum efficiency when the engine is running, with the brake booster being the key component that amplifies the force applied to the pedal. When the engine is off, the brake booster stops functioning. Typically, pressing the brake pedal three times will deplete its remaining vacuum assistance, making the pedal feel stiff due to the lack of booster support. 2. Brake booster air leak or malfunction: If the brake pedal becomes hard to press without prior braking after engine shutdown, or if this issue occurs while driving, it is likely due to a faulty brake booster.
I've encountered the issue of the brake pedal getting harder to press after the engine is turned off several times. This is actually caused by a failure in the brake booster. When the engine is running, it provides auxiliary braking force through the vacuum tube. However, once the engine is turned off, the vacuum source is lost, and the booster stops functioning, making the pedal much harder to press. If left unaddressed, this could lead to vacuum tube leaks or internal booster failures. I recommend stopping the vehicle immediately and avoiding forcing the pedal to prevent damage to the entire braking system. Have a professional repair shop inspect it—they can identify the problem using a vacuum tester. Regularly checking the tightness of vacuum tube connections during maintenance can also prevent such incidents. Safety always comes first.