 According to an April 2013 "Washington Post" news story, the transit agency said that it would forgo updating the 4000-series rail cars and Metro had exercised an option with Kawasaki to purchase an additional one hundred 7000-series cars to replace its 4000-series cars, costing an additional $215 million under the contract.In June 2015 Metro pulled all 4000-series railcars from service following reports that doors were opening during travel; although no systemic problem was located, Metro kept the series out of service for more than a month to address door components that were below acceptable tolerance levels.In July 2015, Metro released a request for proposals seeking a contractor to pick-up and then dispose of all 1000-series and 4000-series cars, as part of its plan to replace those cars with the new 7000-series cars.