1994 Mazda 323 Mazda 323 stutters and feels sluggish when a

Has this problem happened suddenly, or gradually? An exhaust restriction, such as a plugged catalytic convertor can cause this symptom. Along with the cat, the o2 sensor readings should be verified. You can do this with a voltmeter. A fuel filter and/or pump are also possibilies. How are tune up components--plugs, cap, rotor? Have you checked plug wires for resistance using an ohmeter? This can also cause a misfire/bogging problem under load. Good luck