1994 v6 rough idle problems

hello i'm rod new to this and mustangs well here is my problem . rough idle, poor acceleration, poor fuel consumption , here's what i've done so far 1. replaced plugs and wires {#2 cyl had really bad carbon build up on plug} checked compression on 1,2&3 cyl 1 170lbs 2 190lbs and #3 had 165lbs , replaced fuel filter ,, took #2 cyl injector it was dirty cleaned the best i could . the car runs better when rpms are at 2000 or higher when at highway speed in 5th gear i can feel the engine running rough well any speed for that matter under 2000 rpms any ideas?