My 2004 monte carlo ls 3.4 won't stay running. When I crank it over, it runs for maybe a second before stalling out. Thinking old fuel could be a problem, I siphoned out all of the old gas directly out of the hole in the trunk. while doing this, I swapped out the fuel pump, fuel filter, fuel pressure regulator, spark plugs and wires, battery, ignition lock cylinder and ignition switch. The security light is lit up on the dashboard but it isn't flashing, (Not sure if this is supposed to happen). Not sure what else to try.. Maybe bad MAF?