You say on the first pump the pedal is firm but low, and on the second pump,
it's firm but high? Might you be getting "Brake Pad push back"? Loose
wheel bearings let the disk flop around relative to the caliper, pushing the
pads back. On the first brake application you have to move the pads back to
the disk, then they work. On the second application, the disks haven't had
time to flop much, so the pads don't have far to move at all. It doesn't
take much flopping for this to be noticeable. In my FIAT, years back, the
pads could sometimes be heard making a faint high pitched squeaking noise as
I drove down the street. Do a quick "left/right zigzag" and the noise would
be gone.
Stu
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