Bad Accumulator??

[hombre@elp.rr.com (John Erickson)]

What are the symptoms of a bad accumulator?  I've been working on a cutting 
out problem at high RPM and have almost run out of things to check.  The 
whole ignition system is new (it needed it anyway).  The fuel pumps, 
injectors and the fuel filter in the engine compartment are new.  I now 
have a functioning knock box as well.  Almost everything I've changed has 
improved the problem, but its still there.  Somewhere around 4500 RPM it'll 
start to miss a little.  If I stay on it, it will eventually get past it 
and continue on up to redline.  Thoughts?  Accumulator?

John
87 16v
The Land of Lost Bolts