General Motors has announced a new recall of more than 1.3m vehicles due to an electronic power steering threat which “could increase the risk of a crash”, the company says.
The recall follows separate allegations that an engineer ignored GM standards when approving a design change for faulty ignition switches.
That fault has thus far been linked to at least a dozen deaths.
Some 2.6m cars have been recalled for the initial ignition switch defect.
The problem caused some engines to turn off while the car was moving and the company has been criticised for not calling those vehicles back earlier.
On Monday, General Motors informed the National Highway Traffic Safety Administration of its latest recall of US vehicles – including the Chevrolet Malibu and HHR – which may experience a “sudden loss” of the use of electronic power steering.
The initial recall affects 1.6 million cars made before 2007, and last week GM announced it would also cover more than 800,000 made from 2008-11, covering a variety of models including the Chevrolet Cobalt and Saturn Ion.
According to documents provided to a US House of Representatives panel, the manufacturer of the defective switch, Delphi Automotive, said the redesigned versions signed off for use in the 2008-11 models still did not meet GM standards.
That revelation could mean a higher number of deaths are linked to the defect.
“An analysis of NHTSA [National Highway Traffic Safety Administration] early warning report data shows that there are 14 fatal crashes in the recalled 2008-2011 vehicles involving a potential problem with an airbag, steering, electrical or unknown component,” senior Democrats on the House Energy and Commerce Committee said.
GM has linked the issue to 13 deaths, but a report by the Center for Auto Safety has put the number at 303, a figure GM disputes.
At issue is a flaw in the manufacture of the ignition switch that causes the key to shift on its own from the “run” position to the “accessory” or “off position”, even while the car is driving at full speed on the road.
That can shut off the car’s engine and disable the airbags, making steering and braking difficult.
GM chief executive Mary Barra is due to testify before the House about the company’s actions on faulty ignition switches on Tuesday.
“I cannot tell you why it took years for a safety defect to be announced in that program, but I can tell you that we will find out,” Ms Barra wrote in previously released prepared testimony.
“When we have answers, we will be fully transparent with you, with our regulators, and with our customers,” she added.
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