Can the accumulator on this system go "sort of" bad?

I have a '92 Grand Voyager LE with Bendix 10 ABS. When the brakes are applied any more than the lightest touch, the "Anti lock" and "Brake" lights flash momentarily on the dash; and the pump runs EVERY time the brakes are pressed, but does NOT run otherwise and the brakes work fine. I took it to the dealer suspecting the lifetime warranty recall actuator piston assembly or pump (which was already done once on this van before I bought it). $87.32 of diagnostics later they say I have a bad accumulator which they have to fix FIRST before they can test for the warranty parts, for a total of over $500 (including the diagnostics).

I bought a junkyard accumulator for ten bucks and swapped it on (in less than five minutes with an oil filter wrench), but it would not pressurize AT ALL (pump just ran and ran) so I swapped my original back on and it's back to "normal".

I found the accumulator online for about $200, but before I spend another dime, does anyone know if these things can go "sort of" bad? Is it possible for these things to hold enough pressure to operate the brakes well, but not enough to keep the warning lights off? Or is the dealer feeding me a line... A friend had the ABS on his 1993 T&C fixed FREE under the recall at the same dealer the day before I took mine in.

Thanks in advance for your help,
Russ Boyd

› See More: Bendix 10 ABS accumulator