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Last month, Mary T. Barra, the new chief executive of General Motors, told a panel of stern and dubious House members that she first became aware of a serious safety issue with the Chevrolet Cobalt in December, two months before the company announced a recall that would eventually cover 2.6 million cars.
But an email contained among 700 pages of internal G.M. documents released on Friday by the same House committee raises questions of whether she knew more about safety problems with the Cobalt.
The correspondence shows that as a G.M. vice president in 2011, Ms. Barra was alerted to widening problems with power steering in the Cobalt and other models, an indication that she was made aware of safety problems in those cars earlier than she had suggested.
The documents, released by the House Energy and Commerce Committee, detail years of deliberations inside G.M. over a dangerous flaw in the ignition switch of small cars that the company did not disclose to the public until this year.
The committee released only a portion of more than 200,000 pages gathered as part of an investigation into why it took the automaker more than a decade to act on the defect that it now links to 13 deaths.