* Panel also to focus on NHTSA decision-making
* 'Unsettling' information from GM, NHTSA-panel chairman (Adds details on GM questions, NHTSA inaction, background)
WASHINGTON/DETROIT, March 30 (Reuters) - General Motors Co approved ignition switches for cars that have been linked to 13 deaths, even though the parts did not appear to meet the company's specifications, officials of Delphi Automotive told U.S. congressional investigators.
In a memo released on Sunday by the House of Representatives Energy and Commerce Committee, documents provided by GM and a federal regulator provided "unsettling" information, according to Republican Representative Tim Murphy, who leads a subcommittee of the panel.
The memo was released ahead of Tuesday's testimony from GM Chief Executive Mary Barra, who will appear at the committee's first public hearing on the recalls. She is likely to be asked why it took GM so long to identify and address the ignition switch problem.
The information from Delphi officials was detailed in the memo, which is mainly a chronology of actions taken by GM and the National Highway Traffic Safety Administration since the late 1990s and through Friday, when GM expanded its global recall of cars with defective ignition switches to 2.6 million.
GM switches in Chevrolet Cobalts and other models were prone to being bumped or jostled into accessory mode while cars were moving, which would shut off engines and disable power steering, power brakes and airbags, leading to dozens of crashes.
Delphi told U.S. congressional investigators last week that GM approved the original part in 2002, despite the fact it did not meet GM specifications
Congressional investigators also want to know what led NHTSA, as long ago as 2007 and 2010, to determine that there was not a safety defect trend with airbags that were failing to deploy in Chevrolet Cobalts.
"What did NHTSA do to investigate whether a trend existed? What data did it consider," the committee asked.
The Energy and Commerce Committee said GM had submitted more than 200,000 documents on the ignition switches. The panel said the NHTSA submitted about 6,000 documents.
Murphy, a Pennsylvania Republican, did not give details on what was "unsettling" about the information the panel received. His statement was accompanied by the memo, prepared by Republican investigators.
According to one entry of the chronology in the memo, officials of Delphi, which supplied the ignition switches to the recalled GM cars, told committee investigators that GM had approved the part, even though sample testing of the ignition switch torque was below the original specifications set by the automaker.
The committee, according to aides, does not know GM's thinking on why it may have approved a part that did not meet all specifications.
One aide, who asked not to be identified, noted that there were 60 specifications for the switch and it is not clear what the significance is of one specification being below-standard. That is one of the questions the committee intends to ask in hearings.
GM knew as early as 2001 that it was facing problems with its ignition switch, but no auto recalls were ordered until earlier this year.
A February 2005 entry in the congressional committee's chronology illustrates that engineers were grappling with what to do about the defective ignition switches.
"Engineers considered increasing or changing the ignition switch 'torque effort,' but were advised by the ignition switch engineer that it is 'close to impossible to modify the present ignition switch' as the switch is 'very fragile and doing any further changes will lead to mechanical and/or electrical problems.'"
The committee's memo concludes with a series of questions, which likely will dominate Tuesday's hearing with Barra.
"Why did GM approve ignition switches that did not meet its specifications for torque performance? What was GM's assessment of the implications for performance and safety," the memo asked.
It is also not clear yet which GM engineer approved a revision to the ignition switch in 2006, and why the change did not lead to an earlier recall of older model cars to fix the problem. (Editing by Jim Loney, Peter Cooney, Frances Kerry and Eric Walsh)