I can just tell you my story on my Powerpuker, has the same problem, spent the money for a new accumulator, (bad idea) went thru all the testing trees and that’s what it reverted too, Poof, got brakes back!!! Then lasted for all of 650 miles, the wife and I were on a 450 mile round trip ride to see my dad, 200 miles or so in, Powerpuker puked AGAIN, it was the longest most stressful 250 miles home I have ever had, and my back and hip were sore for 2 days from the hard ass pedal, $170 down the drain, wasn’t too happy as I could have spent another $80 and purchased the vacuum conversion kit. Needless to say, FINALLY got her into the garage and that is where she stayed until Vacuum conversion kit came, Keeping it “original” as so many want no longer became an issue when my family’s safety came into play, GM produced a piece of junk, knew they were junk, that’s why there weren’t too many models produced with the Powerpuker, Vacuum brakes have been around for how long??? And flat out work, will never put a Powerpuker back on my car to keep it “original”, they are just a failure waiting to happen at the most inopertune time .