DETROIT - General Motors Co in 2003 and 2004 made changes to redesigned ignition switch parts on four models but did not ensure that older, potentially faulty parts were taken out of circulation, the automaker said in a filing with US safety regulators made public on Friday.
That means that an unknown number of possibly flawed parts could have been used to service GM models brought in for repair at dealerships or repair shops after the redesign was made.
A GM spokesman said that no crashes, injuries or deaths have been reported in any of the four older model Chevrolet Malibu, Pontiac Grand Prix and Grand Am, and Oldsmobile Alero that are involved in the issue.
So far this year, GM has recalled nearly 29 million vehicles, including about 14.7 million for ignition switch problems. Its chief executive, Mary Barra, has testified in Washington four times this year, claiming that GM is observing a new culture on consumer safety. Her latest appearance was on Thursday.
Earlier this year, GM informed regulators that one of its top engineers, Ray DeGiorgio, approved a redesigned ignition switch for small cars including the Chevrolet Cobalt but did not change the part number.
GM has admitted that at least 13 people were killed in Cobalt and other small car models with faulty ignition switches, which could cause engines to shut off while driving, leading to a sudden loss of power steering and power brakes and the failure of air bags to deploy in a crash.
A GM spokesman said on Friday DeGiorgio also approved the redesigned ignition switches in the Grand Prix and other models to which no deaths have been linked.
In the case of the Grand Prix, the GM letter to the National Highway Traffic Safety Administration, dated July 16 shows that in 2004, the part number to the redesigned part was not changed.
For the Malibu, Grand Am and Alero, in 2003 a redesigned part was given a new number, but because the older parts were marked for use by service technicians, it is possible that they could have been put into cars brought in for repair, the letter said.
GM spokesman Alan Adler said on Friday that while older parts may have been used to fix ignition switches in cars,"nothing in our data suggests that there is a danger out there." The Grand Prix, Grand Am, Alero and Malibu were part of a June 30 GM recall that included 7.6 million cars, most of them in the United States, for possibly faulty ignition switches.
DeGiorgio was one of the 15 GM employees pushed out of the company since this year's safety crisis began.
The Grand Prix affected are model years 2004 to 2008, the Malibu 1997 to 2005, the Grand Am 1999 to 2005 and the Alero 1999 to 2004.