Car tries to start but doesnt, it just spits & sputters

I had the same problem all of these models do, but GM wont recall them. Here is what you do if you have not yet, turn to key to on but don't start the engine all the lights in the dash will go on, when they turn back off see if your security light stays on or blinks. If it does its your Pass Lock security system. You can reprogram it using the key, take the key out then put it back in the ignition move it all the way to ON but don't turn on the engine when the lights in the dash go out turn the key back to the ACC position leave it there for ten minutes the light should turn off after about ten min. then turn the key to the OFF position pull it out about 1/4 of the way then push it in and start it up. If this is the problem you may have to do this any time it does not start up.