[akicked]

Hello guys, my F10 2010 535 N55 , around 245k km was getting misfires across all cylinders, one or max two cyllinders at a time. Max was 3 misfires on cylinder 3 and 6 , before the misfire counter resets. Engine was running smooth, no slow start just slight shaking when idle, almost unnoticable. There was only one fault - 101f01, airmass plausability , calculated air masses in the air intake system not plausible - this one seems to be persistent and sometimes triggers CEL, however it has 0 effect on the car behaviour. I changed all the coils and sparkplugs with Bosch and tested for a few days , around 200 km - no effect on the misfires and shaking when idle, so i left it for a paintjob (most likely irrelevant, front bumper had to be removed) and went on vacation.
Friend of mine had to pick it up from the paintjob, he is describing it had a rough idle and after a few kilometers CEL went on, engine started running rough, car lost power and seemed like one of the cyllinders was dead.
When i came back from vacation ISTA showed "Combustion misfiring , several cyllinders"; "Combustion misfiring , cyllinder 1,3,4" fault codes and now when i ran the misfire counter it was going way higher than before. Cyl 1 reached to 12 misfires, before going to 0 , cyl 6 got 10 misfires before going to 0 and so on, and had a very rough idle. Cleared the fault codes and idle got a bit better but still had misfires across all cyllinders. No fault codes for now, only the rough idle and misfires on counter but im assuming its matter of time before it happens again.
Im torn between advices for cleaning / changing injectors,changing hpfp or valve cover, any suggestions? Sorry for the long post but wanted to give as much information as i could. Kinda new to ista but i can do other tests if neccessary to provide more detailed information if needed.
Thanks in advance.