i was having the same sort of problem with my 96 gl and basically i did what had never been done to the car before...i cleaned the friggin' injectors with some o' that nifty lucas injector cleaner and voila and fibiniccio, problem fixed. that and i changed the oil and air filter but that's just reg. matinence (sp?) so if you do that regularily then it's most likely the injectors. unless you actually do have a bad wiring connection, but you said you replaced plug/wires so i was just giving another suggestion.
