Two of Metro's buses suddenly stalled last week, prompting the transit agency to take nearly 200 buses out of service.
The two buses were going less than 10 miles per hour when the engines cut off with no apparent warning, Metro said.
Two people had minor injuries after the incidents, which happened on Wednesday and last Thursday, according to Metro.
Metro said 164 buses manufactured by New Flyer in 2015 and 2016 will undergo safety checks and will remain out of service until the cause of the engine problem is determined.
“We are taking this action, putting safety first, until we fully understand what caused these engines to cut off unexpectedly,” Metro’s Chief Safety Officer Pat Lavin said. “While we understand there may be some customer inconvenience as a result of this action, safety must trump service.”
The buses remain under manufacturer warranty, and New Flyer is sending a team of experts to participate in the investigation.
Metro will deploy a fleet of about 80 reserve buses to help offset the decrease in buses. Commuters may notice some longer wait times between buses, Metro said.
Riders can track any significant delays in service via MetroAlerts email and text messages.