Not fuel outlet, I mean exhaust.
Engines need 2 valves, fuel inlet, and fuel outlet. They also need, if running on OIL, a spark plug, so basically just some SPRK'd metal.
I called it 'Engine' because it works similarly
Reported the stolen version for you, but this isn't really an engine. It's just too unrealistic to be called an engine. My vote remains neutral, giving you a chance to improve. :)