Hi all getting a odb2 code "P0203 injector circuit open cylinder 3" and black matt sooting on the sparkplug causing the car to run rough, its been in the garage a few times for this resulting in new coil pack and throttle body cleaned out and over a£400 bill i imagine they have cleaned the spark plug each visit but each time after about 2 weeks it pops the code up and starts running rough again, i was hoping i could get some advice on swapping injector 3 with injector 2 to see if the issue follows i am no mechanic and have never touch anything to do with fuel rails or injectors so all info would be appreciated to do this,thanks

Well its not a twinair problem..

If you don’t know what you’re doing then give it to a garage, seems likely it would be a bad injector if everything else ruled out, just make sure you’ve tried everything else first.

I believe the injectors need coding to the engine ECU so is likely a job for the garage if you don’t have the means to do this yourself