i have owned the a 1990 cavalier z24 for a little over a month and it ran fine up until a couple days or so ago. everytime i drove the car somewhere the check engine light would come on once the car got up to temperature. i only spent $400 on the car so i didn't want to put any money into it and the car ran fine so i didn't do anything about it. i drove the car home and that was the last time it ran. nothing was different except the check engine light never came one. i thought it was kinda odd but didn't pay it much mind until the next morning i went to start it and it won't run. it rolls over fine but won't fire. where should i start looking first? it's a manual car with a 3.1 engine.