95 running rough

Hi, My 95 with the 3.1 and 3 spped tranny just started to run a little rough when its ideling. It starts ok, but then the idle will fluctuate and sound like it wants to stall. No ecm codes, new o2 sensor, new throttle pos sensor. I think the alt might be going as the inside light was dim today and the guage was low.. started driving and the guage went back up to aboout 13.. any ideas on why its running rough?

If it is just running rough and not pulling any code it probably could stand a tune up,,I would change plugs and wires and give that a try,,I beleive both can be bought for under 30 bucks.