Bleed the brake system....check out the FAQ's if you need some guidance. Brake fluid is hydroscopic (picks up water) so maybe your fluid has been contaminated/degraded over time.

A1C Hodges, Christopher Active Duty USAF Sheppard AFB Texas;Westover ARB Chicopee, MA NECEG "Troll" formerly owned 2000 SVT Contour, with all kinds of goodies;)