Welcome to 2CarPros. How does it drop to the floor? Hold steady pressure on the pedal and it sinks, or does it just drop to a low level and then the brakes work? Does it have ABS? If the first one it is likely that the master cylinder had some crud and rust in it and when you were bleeding the brakes it drug the internal piston over that and damaged them so they now leak past instead of holding. If it's the second symptom and it has ABS then air is likely trapped in the ABS system. To bleed that you need a scan tool that will cycle the valving in the module while you use a pressure bleeder to force the fluid through the system. Manual or vacuum bleeding will not work as the system cycles the valving from side to side and end to end, not one corner at a time.
Saturday, July 6th, 2019 AT 11:46 PM