I have a bmw 323i with bosch Kjetronic, i have

I have a 1982 bmw 323i with bosch Kjetronic, i have replaced the warm up regulator & the cold start air regulator, the injectors have been taken out for cleaning/ pattern check and they were not very good, after operation on the hand pump they were better, is it better to replace them as they cannot be dissmantled? symptoms are irratic speeds when cold and when up to temperature a flat spot between 2500 & 3800 rpm also juddering at these revs when cruising, when accelerating hard over 4000 rpm there seems to be no problems, although there is a lack of power generally.