no oil on right bank injector weeps

1997 ford with a 7-3 diesel drivinng along fine then all of a sudden truck starts missing, put truck in shop removed valve covers to check injector harness, everything appears ok with wiring, no burnt ends or anything. started truck with valve covers off and let idle. observations as follows 1. on left bank oul comming out of weeps like normal. right bank no oil comming out of any of the weeps. 2. unplug injector harness from left bank engine starts missing worse. unplug either of the right bank injector harness plugs and no change in engine performance. i am not sure if this problem is electrical or oil related- oil change done two weeks ago w/ no problems truch has sriven 500 -700 miles since oil change- i own 4 of these trucks and have never seen this problem with the oil weeps. any ideas fellas ????