HELP!! Rough Idling - No power in low RPM's - HELP!!

I have a 95 2.7L 4cyl with about 177K. Ran like an absolute champ up until about a month ago when the alternator went. I replaced the alternator along with all three drive belts and the harmonic balancer. Just finished those repairs yesterday. Took it out and drove like old times for about an hour and then on my way home, it started to hesitate in the low RPM's - 700-1500 RPMs. The only way I could seem to get any power was if I floored it and sort of pushed through the hesitation in low RPM's. By the time I got it home, it would barely stay on at all. Now when I start it, it shoots right up to 1100 RPM and idles for about 15 seconds and then drops right down to about 500 RPM where it struggles for about 30 seconds and then after about a minutes shuts off. So, I thought ignition first. Replaced all fours plugs, wires, distributor cap and rotor. NO improvement. Does anyone have any suggestions? Fuel injectors, air leak somewhere maybe? Any help appreciated. Could this be related somehow to the alternator issues? It seems like two independent problems electric and ignition? Thanks.

 

did you replace the ignition coil