df90 fuel problem

[angler0520]

hi guys i am working on a friends boat with a df90 on it it is starving for fuel i have cleaned the filter inside the vst on the bottom of the electronic fuel pump and replaced the canaster filter on top of the vst i have the fuel rail off and it was full of junk i balive there is a screen on they injectors??? i was wondering if i put the injectors back in the rail if there was a way to test them like just using jumper wires and a battery so i can see them fire and see if they are cloged???????? i just was looking at the material that came out of the fuel rail and it loked like metal so i put a magnet up to it and it sure is what does this mean?????