Not to be a stickler for rules, but tech questions should go in the tech section. Keeps the forums a little more organized. But to answer your question, and from your other thread, your EGR is shot. Replace or remove it alltogether. A bad EGR will cause the symptom's you've described.
306 with all bolt ons, letter cam, ported E7's, T5 swap, full exhaust, 3:55's, 2" drop, and the worst paint you'll ever see or feel.
Dyno'd 300/316, 2745lbs-track scale
Best ET………12.4@108, 1.66 60ft on 8" ET Drags.
24 mpg (combined)