Can anyone help with a running problem I am having with my 1989 Firebird?

My Firebird (1989, V6, 2.8L) has had a running problem lately, and I can't figure out what it is. I've heard MAF, TPS, and EGR, to this point. The MAF was just fixed and it ran better, but was still not running well. It has been dying while idle if I do not rev the engine, even at red lights, and this includes idling rough. It does start back easily, though. It also will jerk while driving down the road, particularly going uphill and trying to maintain speed or speed up. (Note: I thought at one point it may be the transmission because of the jerking while accelerating, but I had that checked and the transmission is in great shape.) Does anyone have any ideas as to what could cause this problem? Any help would be appreciated.