Hello all m having some issues with my breaks the pedal starts out good but then slowly goes to the floor. I have checked for leaks bleed the breaks and nothing. So I figured master cylinder was junk but I swapped it out with a reman from Napa and nothing changed. Any ideas

 

Air in the system? How did you bleed the brakes?
You need to first bench bleed the master before putting it in, then gravity bleed the brake system. Then you need a capable scan tool to bleed the ABS system then you need to gravity bleed the system again.

 

And then you will need a drink...