Every one of Metro's new 7000-series rail cars needs to be rewired, according to an internal review first reported by News4’s news partners at WTOP Radio.

The transit agency paid almost $1.5 billion for the trains.

While the wiring problem isn’t a safety concern, it could cause unreliability.

A report from Metro quality assurance found all 548 cars have wire crimping defects undetected by the manufacturer that could cause lengthy delays and poor reliability. It’s estimated to take a year to fix them all.

The report also found 200 of the 7000-series cars need additional repairs estimated to take two years to complete.

“Another problem among many that Metro seems to be having,” rider Peter Kissel said. “We need all of the jurisdictions to step up and fund Metro like they were supposed to do.”

“Metro’s 7000-series rail cars remain by far the most reliable rail cars in the fleet, traveling nearly twice as many miles (141,386) between delays as all other railcars combined (72,690),” Metro said in a statement.

Metro said it is working with the manufacturer to inspect and fix the cars.

“The inspections will be performed during the maintenance process at no additional costs to Metro and will have no impact on service,” the statement said.