The problem in the summer of 2002 was due to cracks found in the dampers (shock absorbers) that limit the 'rocking' of the cars back and forth. It was several weeks, maybe more, before they got all the issues resolved.

At this point, I don't think anyone knows when the Acelas will get back on track. The Acela manufacturer(s) and Amtrak need to have a "come to Jesus" meeting and figure this out. I'm pretty sure Amtrak won't have to pay a dime for the repairs, but I wonder who pays for the lost revenue.....