abs problems

[slam80sr120604]

hey
i just replaced my hyroboost with a junk yard one
i have brakes but when i step on the pedal the brake light comes on and then the abs light comes on and then they both go out
you can feel a vibration in the pedal when that happens
need some help
thanks

 

[OldSchool1]

The unit that you installed may be bad.

To rule this out, you should replace the accumulator with a new unit and then completely flush the system with about two quarts of fresh fluid.

A very fast and rythmic feedback of the pedal could be your Anti-loc Braking System doing it's thing to make sure your wheels do not lock up.

When these are done, let us know how you made out.