The National Highway Traffic Safety Administration is urging owners to use only the ignition key with nothing else on the key ring and to get the problem fixed as General Motors is widening a massive recall that involves the ignition on some of its vehicles. Engines would just stop while the cars were being driven. One-point-six million cars and crossover SUV's including six Chevrolet, Pontiac and Saturn models are being called in for service. The automaker says that something as simple as a heavy keychain or a sudden bump to the ignition can cause the engine and electrical system of some of its vehicles to shut down -- and without the electronics, the airbags won't deploy. GM acknowledges that 13 front-seat passengers have died in crashes related to the problem. Six Chevy, Pontiac and Saturn models are involved in the recall -- Chevy Cobalt, Pontiac G5, Saturn Ion, Chevy HHR, Pontiac Solstice and Saturn Sky.