Yesterday while driving my check engine light came on. After stopping at my house for a couple of minutes I tried to start my car but it would not start; only crank over. I decided to wait for a couple of hours to try it again and my car started with no problems. I decided to test it out again today and sure enough when I turned off my car and tried to start it back up it would crank over, but would not start. I have to wait awhile in order for my car to start up again. What could be the problem?