Perhaps a vacuum leak. Check vacuum lines and also around the intake manifold
Check you battery
Is it overheating. Cheapest is a bad waterpump. Or worse, headgasket blown, or bad motor. Bad crankpulley could cause not to start, but would not cause overheating unless belt came off.
I'm looking for help.The secority light is on car won't start.
look on passenger side, front fender. Should see a small red box, flip it open.
if I'm thinking correctly its a bracket...
it sounds like your neutral safety switch
start the car. the alarm should turn off
wash all the oil off then start the engine and watch for new oil Oil pressure sensor or oil pan gasket!
Disconnect the battery, wait 5 seconds, and reconnect it. It should start then. When you replace any electronic or electrical, the computer will not realize it until the car's computer is "reset". To do this, you must unhook, and the rehook the battery.
Bad ignition module, crank sensor, or coil pack. Especially if yours is equipped with the magnavox coil pack vs the delco coils which have 3-seperate coils.
Check out this website, it is the best one I have seen and I'm doing it to a '71 VW Bus right now. http://www.instructables.com/id/Push-Button-Ignition-for-your-Car/
check the battery. mine wont start if its 0 or colder.