i have a chevy malibu 2012 LS. i havent been able to start it in months and cant really afford to bring to a mechanics shop at this time. i have changed the starter, checked the alternator, its not the battery and the fuses are fine. i was told its possible the killswitch was triggered at one point , but wouldnt that reset itself? Before it stopped running the co2 sensor was on would that have something to do with it? please help as iam not mechanical at all.