Just replaced LS430 brake master cylinder. During the procedure, 2 brake lines has to be removed from master cylinder to ABS Solenoid. After install the master, I bleed the master and got some air out of it. Then I bleed all 4 wheels over 30 times. Just don't seem to get air out of the system. At the first pedal pump, the pedal is slightly low and 80% firm. Second pump, pedal rise up and 90% firm. Any suggestion ?