2010 ford mustang convertible turning over but no start and a small back fire when trying to start it?

[Luna The Wolf2213]

Hi all, I have a 2010 ford mustang with the 4.0 liter v6 that has around 201k miles on it. The car when you try to turn it over it will turn over but it is not starting and when you try to start it, it has a small backfire coming from the engine. When you turn the ignition switch on you can hear the fuel pump come on, I disconnected one of the fuel lines and it’s getting fuel when you try to start it. The key that came with the car when I bought it a few days ago isn’t the original key. The key won’t go to the lock/off position and come out of the ignition with the battery connected but will come out/ go to the lock/off position when the battery is disconnected. The car also hasn’t thrown any codes when I check it on a scanner

 

[White Horse GTCS 2008]

Good luck with your investigations Luna.
Sorry, I don’t have a diagnosis- I’m also a junior member and have limited knowledge te such issues.
Though you have posted on the right forum.
Wishing you luck finding the solution.