just thoughts...
Did you bleed the Master Cyl. first, and seperately?
Did you lightly tap the calipers at intervals during the bleeding process?
Did you pattern your sequence, rr, lr, rf, lf?
ABS? If so, the HCU, hydrolic control unit must be bled after the master cyl, and beofre the lines, seperately.
Don't "pump up" the brakes to do the bleed, it compresses bubbles, and makes it even harder to manage the air out.
Like I said, just some thoughts. About eight years ago in a truck shop I had to learn about bleeding the Mast Cyl seperately the hard way. I thought it was to bleed it in place, right along with the rest of the system and do just fine. Sometimes you can slide by doing that, and sometimes not.
Heed the warnings of the ABS systems being under high pressure, and do all of you operations in the key-off or battery un-hooked position.
Best of luck with your repairs.
TheRasper.