For anyone with the sudden sinking pedal.
I had the pedal go to the floor with my son on a learner's permit driving. Slipped into intersection and luckily nobody was coming from either way.
Repaired under warranty with brake booster replaced.
Few months later went over rough railroad crossing and pedal again went to floor with no power brakes. Paid ford dealership another $1200 to repair with new brake master cylinder installed.
Three months later hit a patch of snow and antilock activated and same problem, no power brakes. Ford said good news, we've replaced everything so should be no charge this time. Days later call and say it's the abs control module stuck valve, $1200. I called bs and said pull her out and give me the keys. I may have used less civilized words.
Watched a lot of youtube stating I should jam on brakes to activate and "unblock" the abs manifold/block/module. Tried and no luck. Finally, read further and someone suggested not only jamming brakes on gravel road in forward to activate abs but also doing in reverse. Tried in reverse and pedal IMEDIATLLY came back to normal. 1 1/2 years later 30k miles later and free youtube fix still going with no problems and $2400 stealership fixes were a waste and never did fix problem or protect my family. After you make ford replace the booster under the extended coverage customer satisfaction program, find a gravel road, drive her up to 25 mph a couple of times and jam the brakes, then do same in reverse (no need to be at 25 here) then send me the ,$2,400. Only kidding. Those sacks of xxx at stealership will try to charge you that much and dont really fix, they just bleed and temporarily mask the problem. Just walk in and tell them Ken says they suck.