Check or change tps sensor, rear side of throttle body, my 97 was doing the same thing, i guess its a worn out spot in the sensor where you usually hold the pedal at, like driving at a constant speed, that is when mine would do it , going along just fine and then sputter , ild have to 3/4 pedal it and it would then take the gas. Not saying its your issue but thats what it was with mine. Before i changed the tps sensor, ild unplug the o2 sensor before at the down pipe on exhaust and try to drive it with the sensor unpluged, check engine light will be on but if it doesnt sputter than its def the o2 sensor.
