omniserv

I have posted this question on here before, but thought it best to start a new thread. I have a 1987 NA that runs smooth at idle and actually seems to run fine all together, however at about 2000-3000 RPM's it seems to almost stumble or miss out. Maybe a better way to discribe this is just a lack of power. This car has 130k miles on it and I've done the following to try and fix it. New plug wires New Distrib. Cap New rotor cap New Spark plugs Timing belt replaced 10K miles ago. Set timing New air filter New fuel filter New Injectors and fuel rail (thanks to the recall) lol Test fuel pressure (30-40PSI) I have a o2 sensor ordered and Monday will have it put in. I read in the manual that you can unplug the 02 sensor and drive the car to see if it runs any differant. I did this and it did seem to run just a little better, guess Monday I'll find out if it's the o2 sensor or not. Does anyone have any other idea's? Chris