Volvo S60 D5 Problems with injectors

Dear Volvo friends, my Volvo S60 (BJ. 09/2003, 180,000 KM) is slowly driving me crazy. The problems started with light vibrations on the steering wheel in the speed range 1400-1700 u/min. especially under load and cold condition. After about 1 month it was clearly audible that the engine does not work properly – in idle run it nails, in the lower speed range it is powerless and swallowed itself. The moose father found that 4 of the 5 injectors do not have to work properly and be replaced – measured values of 5,7-30 mm3, (reference value max. 3 mm3), only one was still fully functional. The best thing was to replace all 5 – cost point 2000€!!! Meanwhile 4 of 5 injectors have already been replaced (at Bosch, all general overhauled), but the problems have remained the same. What do I do? I don’t know any more! If I had stayed right with the Volvo. What does the professional community say? Need reasonable and useful suggestions.