– General Motors chief executive Mary Barra on Tuesday deflected a barrage of questions on Capitol Hill about the automaker’s failure to fix a deadly ignition-switch flaw, telling lawmakers that she was unaware of the decade-old problem until early this year.

While she repeatedly apologized for a defect that GM has blamed for the deaths of at least 13 motorists, Barra also repeatedly ducked lawmakers’ sometimes testy queries, saying she is awaiting the results of an internal investigation.

A GM lifer who became the company’s top executive in mid-January, Barra took pains to make a distinction between the cost-conscious “old GM” — which, she admitted, missed a series of red flags and may have engineered a coverup — and the post-bankruptcy “new GM,” which Barra said is focused on customer safety.

“I cannot tell you why it took years for a safety defect to be announced,” Barra told a House Energy and Commerce Committee investigative panel. “I can tell you that we will find out.”

Feinberg hired

Barra announced that Kenneth Feinberg, the lawyer who has helped mete out payments to victims of the Sept. 11, 2001, terrorist attacks and to victims of BP’s Gulf of Mexico oil spill in 2010, had been hired by GM to “explore and evaluate options in its response to families of accident victims.”

The move suggests that GM expects to face additional claims on behalf of people killed or injured in the recalled vehicles. Feinberg said Barra has asked him to examine options for compensating victims of the defect, which could include a broad settlement fund.

“Over the next 60 days, we hope to propose some objective claims-resolution approach that meets the needs of the victims, the company and the public interest,” Feinberg said in an interview.

GM has recalled 2.6 million Chevrolet Cobalts and other small vehicles because of the faulty switches. Lawmakers said GM could have fixed the defective switch for as little as 57 cents per vehicle. Still, the automaker waited more than a decade to issue a recall, despite mounting evidence of a ­problem, including 133 complaints to dealers and numerous legal settlements paid to families of people who perished in related crashes.

Barra’s testimony seemed to do little to mollify lawmakers, many of whom appeared to have scoured the thousands of pages of documents the company submitted to congressional investigators. One after another, they grilled her about questionable company decisions, such as installing switches that did not meet GM’s technical specifications and quietly approving a new switch design in 2006 without assigning a new part number or initiating a recall.

“Ms. Barra, I know this isn’t the most enjoyable situation for you. But we’re in a situation where we don’t trust the company right now,” said Rep. Gregg Harper, R-Miss.

The panel also heard from David Friedman, the acting head of the National Highway Traffic Safety Administration, which also failed for years to recognize the problem. Friedman pointed the finger at GM for not providing regulators with timely information that could have led federal regulators to order a recall.

“Our ability to find defects also requires automakers to act in good faith and on time,” Friedman said.

Asked by Rep. Diana DeGette, D-Colo., whether GM had acted in good faith, Friedman said the NHTSA has opened an investigation “to answer that exact question. And if we find they were not, we will hold them accountable.”

The hearing took place in a room packed with observers, including the family members of people who died in the recalled vehicles. Photos of about a dozen crash victims — smiling young women, a Marine in his dress blues — were propped on a ledge at the back of the room.

Barra, who held a tearful meeting Monday night in GM’s Washington offices with nearly two dozen family members of crash victims, expressed her “sincere apologies to everyone who has been affected by this recall … especially to the families and friends of those who lost their lives or were injured. I am deeply sorry.”