DETROIT, Michigan - General Motors' deadly ignition switch flaws emerged from an effort to improve its cars.A GM switch engineer testified in a lawsuit deposition early in 2013 that, as the automaker began developing small cars in the late 1990's, it listened to customers who complained about "cheap-feeling" switches that required too much effort to turn.So, GM set about making switches that would work more smoothly and give drivers the impression that they were better-designed. However the switches were too loose, touching off events that led to at least 13 deaths, more than 50 crashes and a raft of legal trouble for the Detroit automaker.'SWITCHES CAUSED ENGINES TO STOP'Former US Attorney Anton Valukas, hired by GM in March 2014 to investigate the switch problems, told a congressional sub-committee in June 2014 that GM wanted each small-car ignition to "feel like it was a European sports car or something".GM, after years of lagging behind Japanese automakers, was eager to make better, more competitive, small cars but the new switches in models such as the Chevrolet Cobalt and Saturn Ion could unexpectedly slip from "run" to "accessory," causing engines to stop.That shut off the power steering, making cars harder to control, and disabled air bags in crashes. GM said the problem caused at least 13 deaths but some members of Congress put the death toll as near 100.The problem led GM to recall 2.6-million small cars in February 2014 and forced the company to admit it knew about the switch troubles for more than a decade before taking action. It has sparked investigations and prodded GM to review other safety issues.By July 2014, it has issued 54 recalls involving 29-million vehicles.DECADE-LONG PROBLEMThe Associated Press traced the history of the problem using Valukas' report as well as a deposition of GM switch engineer Ray DeGiorgio that was released by a House sub-committee. The deposition was also released by lawyers suing GM but DeGiorgio's comments were redacted in that version.In a wrongful-death case in the US state of Georgia DeGiorgio testified that he started out trying to make the switches easier to turn but from the beginning he was consumed by electrical issues in the switch, not its mechanical parts.When switch supplier Delphi pointed out tests showing the switches turned too easily DeGiorgio told Delphi not to change them because he was concerned that mechanical alterations would harm their electrical performance, according to Valukas.Delphi spokeswoman Claudia Tapia said the company was not commenting on details of the GM recall.In the end, DeGiorgio approved switches that were far below GM's specifications for the force required to turn them. The result was a smooth-turning key but one that could slip out of position. Several years later DeGiorgio signed off on a design change that fixed the problem but he didn't change the part number, which stymied later attempts to figure out what was wrong with the cars.GM ENGINEERS DISMISSEDRepeated efforts by AP to reach DeGiorgio have been unsuccessful. He was one of 15 employees dismissed by the company in June 2014 because of the recalls. At a House sub-committee hearing, also in June, new GM CEO Mary Barra didn't mince words when lawmakers asked her about DeGiorgio's statements to Valukas and congressional investigators.Barra said: "I don't find Mr DeGiorgio credible."GM spokesman Greg Martin said Valukas' report cited several opportunities that the company missed to fix the problem before the switches went into production. He said: "It should never have happened, regardless of the reasons for changing the initial specifications."Subsequent safety reviews also found ignition-switch trouble in other cars. The company issued five recalls for 17.1-million cars with switch problems in 2014.Among the recalls are 3.4-million large cars - among them the Chevrolet Impala - which had switches DeGiorgio worked on. GM says the combined force of a large bump and a swinging key chain could cause those switches to slip and kill the engine. GM is changing the keyhole from a slot to a small circle to limit how much key chains can swing and tug at the ignition.'IT'S STILL POSSIBLE FOR IT TO HAPPEN'Unlike the Cobalt and Ion switches, GM said, the ignition switches on the large cars met its specifications, and the key design was the problem. GM says it conducted eight different driving tests with the new key and the ignition didn't move out of the "run" position in any of them.Some experts still believe the switches can still slip out of "run" too easily. Erin Shipp, a mechanical engineer who helped to uncover the small-car ignition switch problems while working for attorneys suing GM, said: "They're finding that it's still possible for it to happen."