Hello fellas!

I have an issue with my mustang GT 2007. I bought this model because I love it, but I have had some issues with it. The gearbox (automatic) was replaced recently and then a misfire issue showed up. I can't identify where it comes from or why. I changed the spark plugs, the ignition coils, I have done the service to the injectors, I got an electrician to check the wires and electricity, I have changed also the engine and transmission mounts since the ones before were broken, I...

Unidentified failure (misfire) reason