WASHINGTON — Federal regulators were under fire Monday for failing to act quickly on evidence that faulty ignition switches in some General Motors cars were killing the engine and preventing air bags from inflating in accidents, contributing to 13 deaths.
Consumer advocates — including Joan Claybrook, a former National Highway Traffic Safety Administration chief — called on the agency to investigate why it did not demand that GM recall cars after learning as early as 2007 that an ignition defect could inadvertently stall a vehicle, disabling its air bags.
‘‘While GM bears complete responsibility for failing to recall these vehicles by 2005, when it knew what the defect was and how to fix it, NHTSA has responsibility for failing to order a recall by early 2007, when it knew what the effect was and how to fix it,’’ Clarence Ditlow, executive director of the Center for Auto Safety, wrote to NHSTA seeking an independent probe of the agency’s response. The center and several other groups are also calling for a congressional investigation.
NHTSA officials defended the agency’s actions, saying they have long been concerned about potential stalling. The agency launched probes of suspicious crashes caused by the faulty switches, but investigators struggled to pinpoint the exact cause of the accidents amid a fog of complaints and complications, including the introduction of a new air bag around the time of the earliest incidents.
‘‘NHTSA receives and screens more than 40,000 consumer complaints each year and pursues investigations and recalls wherever our data justifies doing so,’’ the agency said.
The demands for hearings and investigations of NHTSA came as GM on Monday named a former federal prosecutor to head its inquiry into why the automaker waited more than a decade to recall vehicles equipped with the problematic ignition switches, which now number more than 1.6 million.
Anton ‘‘Tony’’ Valukas, chairman of the law firm Jenner & Block, will work with GM’s general counsel, Michael Millikin, on the probe.
GM chief executive Mary Barra said she has demanded an ‘‘unvarnished’’ picture of GM’s actions.
The automaker, which has been enjoying a resurgence following its 2009 bankruptcy, issued the recall last month to fix the switches, which sometimes cause cars to turn themselves off, stalling the engine and shutting down electronic components. The company has said the problem is more likely to occur when cars go off the road or when the ignition switch is jostled by, for example, the driver’s knee or an overloaded key ring.
GM has linked the problem to 13 deaths, and consumer activists suspect the total could rise. The recall covers the 2005-2007 Chevrolet Cobalt, 2003-2007 Saturn Ion, and the 2006-2007 Pontiac Solstice, Saturn Sky, and Chevrolet HHR.
The NHTSA is conducting its own investigation. Last week, it issued an order to GM, demanding answers to 107 questions about what happened in the decade between the first indication that the switch was faulty and last month’s recall.
In what some officials called an unprecedented request, NHTSA wants the names of employees involved in investigating the problem. It also wants details about complaints GM received from owners, the names and correspondence of employees involved in the company’s attempts to fix the problem, and reasons why proposed design changes were not implemented in 2004 and 2005, soon after the problem first surfaced.
In 2006, GM disclosed the problem to dealers in a technical-service bulletin that resulted in repairs to 474 cars. In 2007, a research team looking into the Rose crash informed federal safety regulators about the potential link between the defective ignition switches and the failure of air bags to deploy.
Another seven years would pass before last month’s recall.
‘‘It is absolutely appalling,’’ said Laura Christian, the mother of a girl who died in a 2005 crash, ‘‘that it took so long for this recall to happen.’’