1998 Chevrolet Lumina Rough Idle & Acceleration Hesitation

My '98 Lumina 3.1L has 120,000 but was running good, has always had basic up keep (plugs, oil changes etc.) But never anything like new valve spring job or anything like that. Only as needed repairs. Turned it off, went into a store for 5min, came back out and upon start up was flashing check engine light & idling roughly, randomly for a second or two at a time revving down then beck to normal and when I accelerated was doing the same thing but worse until got up to about 35-40mph then was smooth. Later same day volts light came on, had alternator tested, bad, and replaced that. Has misfire on no. 4 cylinder code now only. Cleaned MAF sensor, still same problem but noticed crack in plastic housing to MAF. Tried a plug wire from my truck on no. 4 but same problem so not the wire, and replaced plugs with no luck. I disconnected MAF while running, seemed to smooth out a bit, then when plugged back in would be extra rough idle for a few seconds, then back to usual rough idle. Don't want to spend $100 if MAF isn't the problem but think other than the coil nothing else seems suspect from the way the problem started so suddenly though. All internet searches point to MAF or coil, or vacuum lines (which I looked over and seemed okay) Any input would be appreciated. Oh and the other day it died three times immediately after starting then kept running and hasn't died again since. Been driving it like this about a month, I'm poor and have a infant son so my $ is precious but don't want it breaking down for obvious reasons too, just want to put my $ in the right place the first time.