[Myn63nightmare]

So I have 2011 n63 so i bought this car from used lot AS is and aftwe i changed all spark plugs i ran into more trouble
the injector for one my cylinders for one of my cylinders showed no voltage after changing plug so i changed the coil with a used but still working coil wiggled the wires around by that fuel injector while i had everything apart when changing that coil and bam i had voltage at injector car ran way better cel light went off but after two days im having issuses again i ran obd2 code and got p144b PD code p0303 code p0463 code the main ones is the p144b pd code and misfires on the same cyclinder the injector was not showing voltage also when i ran test i get like 40 error codes does this seem like the computer itself is failing ..
some of the error codes on bimmerlink/code for my car