Car will crank but won't start in my 2010 ford fusion

Hello, with an engine that cranks and will not start, first see if the "theft" indicator light for the passive anti theft system (PATS) is flashing while you are trying to start. Typically on this vehicle, if that's the case, it will not even crank, but warrants just having a look. Second, you likely have a fuel, ignition or air intake issue occurring. Testing would be needed to find out if you have fuel pressure at the time of the problem occurring. Then, if you have fuel pressure, check for spark at your coils. Ensure you have no air box or air intake restrictions. Once you find out which element is missing, troubleshooting can continue towards finding the root cause and making repairs.