抄來的：

Start your car and press on the brake pedal firmly, but not super hard, and keep the pressure on the pedal. If the pedal gradually goes all the way down to the floor, the master cylinder is bad.

說明慢慢在活塞 （Oring？）有漏。

所有跟帖： 

• 謝謝您！感恩節快樂 -wibblypig0- ♂ (0 bytes) () 11/23/2023 postreply 11:44:30

• 試過了，沒有文中說的這個現象 -wibblypig0- ♂ (0 bytes) () 11/24/2023 postreply 05:53:31