Two O2 Sensors and still the same thing...(Long)

Ok guys here goes, when i first installed my A/F I noticed that when i started the car in the morning the gauge would go to rich and stay there until the idle dropped(car warming up). After about six months the A/F gauge wasnt responding to my accelarator inputs(before-applying gas would make the gauge go rich, then for some reason the gauge was going on its own, not to mention sluggishly)

I changed the origianl O2 with a Bosch one and it worked only when the car was fully up to its operating temparature…no lights were lit on the gauge while it was warming up…no biggie right? Well shortly after the instal of the Bosch O2 sensor, i started to get a code 43 with my engine light on(fuel system…everyone says that its usually the O2 sensor) also my fuel milage went out the door.

I finally replaced the bosch O2 sensor tonight with another bosch one tonight…now this is were it gets freaky…with no check engine light on, the A/F gauge rarily reads rich…also it flcikers so slow between lean and stoich…when the engine light comes on(still code 43) the gauge works GREAT! It cycles between lean-stoich-rich quickly and it responds according to what im doing with the gas pedal…WHAT GIVES??? Sorry for the long post but I have had it with this problem…Thanks