By Jerry Hirsch and Jim Puzzanghera, Los Angeles Times

WASHINGTON — General Motors Co. CEO Mary Barra said Tuesday she wants to find out if key engineering employees at the automaker executed a cover-up or merely erred in not recalling cars equipped with a defective part linked to 13 deaths.

In testimony before a House Energy and Commerce Committee panel investigating why the automaker waited years to fix the vehicles, Barra said she has asked former U.S. attorney Anton “Tony” Valukas to help figure that out.

Valukas investigated the collapse of the Lehman Bros. financial services firm in 2008.

Barra also issued yet another apology for GM’s failure to fix the problem years earlier. She conceded that company officials knew of issues with the faulty ignition switches behind the crashes and deaths for more than a decade.

Barra said she found the automaker’s worries about the cost to fix defective cars “disturbing.” Those concerns were detailed in documents obtained by the House committee.

“That is not acceptable,” Barra said. “Today … if we know that there is a safety defect on our vehicles, we don’t look at the cost, but at the speed at which we can fix the problem.”

Barra said the company has hired Kenneth Feinberg as a consultant to explore and evaluate options for the families of victims of accidents caused by the defective part.

“Mr. Feinberg is highly qualified, and is very experienced in the handling of matters such as this,” Barra said. “He brings expertise and objectivity to this effort, and will help us evaluate the situation and recommend the best path forward.”

Feinberg has previously handled compensation issues for victims of 9/11, the BP oil spill in the Gulf of Mexico, and the Boston Marathon bombings.

“My mandate from the company is to consider the options for dealing with issues surrounding the ignition switch matter, and to do so in an independent, balanced and objective manner, based upon my prior experience,” Feinberg said.

Barra also told the panel that the automaker made “mistakes” in not recalling vehicles with a deadly flaw years ago.

She was to be joined before the committee by David J. Friedman, the acting administrator of the National Highway Traffic Safety Administration.

In written testimony released ahead of the hearing, Barra made no excuses for GM’s failures.

“I cannot tell you why it took years for a safety defect to be announced,” Barra said. “Mistakes were made in the past. We will not shirk from our responsibilities now and in the future.”

Although it knew about the problem as far back as 2001, GM only in the past two months has recalled 2.6 million vehicles to replace the defective ignition switch, which is now linked to 13 deaths. The switch can unintentionally turn off the vehicle and disable its airbags.

GM faces investigations from the NHTSA and the Justice Department into why it did not recall the vehicles sooner.

Lawmakers are set to quiz Friedman about why the safety agency didn’t force GM to recall the vehicles earlier. Documents show that the NHTSA was aware of the problem.

In his written testimony, Friedman said GM had failed to provide regulators “critical information” that could have triggered recalls years earlier. Only recently did GM provide “new evidence” that made it clear that the ignition problem could disable air bags, he said.

Meanwhile, families of victims of fatal crashes of the GM compact cars in question on Tuesday sharply criticized the automaker for delays in recalling the vehicles and called for legislation to prevent a repeat of the situation. About two dozen family members gathered in front of the Capitol to make their case before Barra and Friedman testified.

The families were joined by four Democratic lawmakers who want to toughen laws governing the disclosure of auto defects.

Photo: Siemens PLM Software via Flickr