GM-GMC: 1993 Chevy Suburban 350 TBI hesitation, chevy suburban, vacuum line

Question
My 1993 Chevy Suburban idles great but if you press the throttle just a tiny bit it runs extremely rough if it doesnt stall out it fixes itself in about 5-8 seconds but if you are just trying to back up with a little throttle you have to hit it pretty hard to keep it running good. other than that if you give it a fair to heavy amount of throttle its fine. one thing i did notice is that when i took the air cleaner off and played with it, when it was running rough there was no suction sound and as soon as the suction sound came back it ran fine. Please help i am stumped. Also i plugged in the vacuum line to my EGR valve because it was unplugged but it didnt make a change.

Answer
There are a number of things that can cause a rough run condition like what you are describing.  
A faulty or plugged idle air control (IAC) - it is mounted on the side of the throttle body.  carefully remove it and clean the pintle and the passages in the throttle body.
A faulty egr valve - remove the egr and check for carbon build up causing the egr valve to remain open (even slightly)
Timing- check your base timing (with the SPOUT line disconnected)
Fuel pressure- check your fuel pressure should be in the 13psi range

I would start with the one you find the easiest and work through them, testing after each one to see if you have fixed the problem.

Hope this helps