CONCORD, Calif. (KGO) -- An unsolved power problem that led to months of commute delays last year appears to be back. BART is working round-the-clock Friday night to identify and fix the mysterious issue that damaged 22 cars between North Concord and Pittsburg - Bay Point stations.
Commuters headed to Pittsburg - Bay Point waer greeted by yellow-vested BART workers at the North Concord - Martinez station, one stop short of their final destination.
RELATED: BART service back to normal after 22 trains short-circuit
An electrical problem on the tracks between those two stations seemed to affect longer trains. So BART used shorter, 5-car trains, to shuttle people between North Concord and Pittsburg. It was puzzling for some riders.
"They just said they're having electrical problems at Pittsburg-Bay Point and we have to switch to a shuttle train, just confusing," said Oakland resident Allena Alasad.
She was trying to get to the last stop on the line to pick up her son and go back home to Oakland. She had to have her babysitter drive him there before heading home.
Some commuters told us they could smell something burning on the ride to the North Concord station.
"We caught the BART in Fremont. And all the way up here it smelled like burning break fluid," said rider Jamie Chavez.
"Smelled like something was burning, almost something like electrical, or burning breaks," rider Rodney Hackney told ABC7 News.
RELATED: BART continues to work on electrical problem in East Bay
The problem started around 10 a.m. Officials spent the day tracking down what's causing the electrical systems to go haywire.
Last year, mysterious power surges damaged dozens of cars. The problem eventually went away, even though the exact cause has not been found.
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