6.2 runs rough hard starting
 

hey guys im 18 and have alot of experiance with smalll engines. diesels are another story. i have a 6.2 and it leaked fuel through the valley... so i bought a 35 dollar pump off ebay it was an as is buy. well i slapped it together and it wouldnt fire. so i took the top cover off the pump and filled it with diesel, and it ran hard when i throttled up it rapped out quickly at half throttle but it idled. when i got the pump i turned the fuel screw up and i noticed that the arm that pivots when the throttle lever is rotated, it pushes a little rod in the pump. well the ajustment screw was all the way out. on my old pump it was in all the way? i took it on a half mile test drive and it died and woudnt start please help

Was it the fuel pump or injection pump??