Injector circuit open cylinder 4

[Anthony_295]

Hello, I am new to this and forums in general. I will try to make this short and simple. I'm looking for help in diagnosing a problem with one of my injectors, more specifically injector number 4 apparently. I say apparently because I've had it replaced with a brand new injector twice and is fairly confident that the injector is not the problem. I must add, the first time we replaced the injector, the problem was fixed for about 24hrs before it reverted to not working again so the mechanic assumed the new injector was faulty so he replaced it again free of charge with a new one. Is it likely 2 new bosch injectors failed hours after being installed? I've also had the wires tested and no issues was found with the wiring. I've swapped the spark plug coils around and the issues still persist with injector 4. I haven't checked the spark plug itself but wouldn't that throw a different code if the spark plug was the problem? The issues im having is loss of power, jerky, stuttering, shuddering, laggy and slow to accelerate. This does improve once the car is warmed up though. I have scanned the computer and the error codes I get is a P0204, injector circuit open cylinder 4. Secondly, im getting a error code Mass air flow sensor reference voltage. Could the mass air flow sensor be the problem? I've had this error code for a long time and the car was running just fine with it. If the mass air flow sensor is the problem, why is it only affecting cylinder 4 injector? Is the cylinder itself gone? This is weird because the rev needle is also very steady and is not dancing around or behaving erratically and the car idles fine. One thing to note, I have a Ramair induction kit fitted but I've cleaned it regularly and oiled it. Another thing to note is that this problem occurred overnight. I woke one morning as normal, started the car and this started happening. Does anyone have any ideas of what could cause this problem?

I will attach a screenshot.
Thanks for reading