Hi! I´ve a 5.4 2010 FX4. I´ve a problem with the brakes, the pedal goes to the floor, I have a hard pedal first half of the way, and if you press harder, goes to the floor.
I´ve make a bleeding of the system, check the vacuum, used also a smoke machine looking for leaks, checked the fuses 36, 47 and 54, but everything looks ok. I don´t have any codes (checked with Forscan).
I checked with Forscan the readings regarding to ABS and they are as in the images. I don´t know if they look correct or something is not working correctly. First image is engine running, brake pedal resting, second with the brake pedal pressed to the floor. Any ideas of whats happening with the brakes or what to check?
Thank you.

 

Today I made a module bleeding with FORScan, no luck, still soft pedal. The ABS pump works.

 

Sounds like a bad master cylinder to me.

 

I’ll check, but while bleedeng the module, pumping with the pedal 2 seconds, release, pump, release ….. there was a point the pedal got realy hard.

Do you think the reading of the valves when pressed the pedal is right?

 

Wasn't master cylinder failure a recall issue with these trucks many years ago? Or possibly just replaced within the warranty period?