1993 Mazda Protege Missing

I'm experiencing what I would term a "miss" in the engine at random times. The most noticable is at freeway speeds in 5th gear when trying to accelerate. It will not gain speed and actually begins missing. Sometimes at lower speeds it will do the same thing, but seems to get better with more rpms. I have replaced plugs, wires, cap, rotor, fuel filter, air filter. I suspected fuel pump, but it never completely dies and always starts. I ran diagnostic by jumping gnd and ten and get codes 1 (no ignition pulse signal), 8 (egr position sensor), 15 (left O2 sensor), and 17 (left O2 feedback system). Could any of these be causing the hesitation/miss? Thanks!