Hi and thanks for using 2CarPros.
If there are no leaks, the master cylinder is most likely bad. Take a look through this link. It discusses causes of the pedal to go to the floor.
The first portion of the link discusses fluid loss, but toward the bottom, it describes more in detail what I mentioned. I feel that is the most likely cause.
Let me know if this helps or if you have other questions.
Wednesday, November 28th, 2018 AT 2:47 PM