replaced the master cylinder and braking has improved, but still goes to floor when held

2009 LINCOLN
100,000 MILES • 3.7L • V6 • FWD • AUTOMATIC
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THOTRODDER
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Brake pedal goes to the floor. I replaced the master cylinder and braking has improved, but still goes to floor when held.
Nov 19, 2016 at 3:13 PM
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MHPAUTOS
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Did you re-bleed the entire brake system after replacing the master cylinder?
Nov 20, 2016 at 12:38 AM
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THOTRODDER
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Yes.
Nov 20, 2016 at 4:58 AM
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MHPAUTOS
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if you pump the pedal and hold it will it stay up? does it fall away under light pedal application?
Nov 20, 2016 at 12:32 PM
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THOTRODDER
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It will start to fade to the floor.
Nov 20, 2016 at 7:41 PM
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STRAILER
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Hello,

It sounds like there is air trapped in the ABS unit and you must have a scanner to open each valve to bleed it, this does happen all the time but it does happen.


Please let us know happens so it will help others.

Best, Ken
Nov 22, 2016 at 8:04 PM
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