Oldsmobile/Buick Repair: 97 olds achieva oxygen sensor, olds achieva, oxygen sensor

Question
My check engine light came on and i took my car to autozone to get the code read. Had 3 error codes for bank 1 sensor 1 o2 sensor. Replaced sensor, check engine was still on. Went back to autozone to get the code read again, and again error to bank 1 sensor 1, so they gave me another o2 sensor thinking the first one was messed up. Installed the second one, still the check engine light was on, so i headed to autozone again, they read the code and i got a code for insufficent activity. I drove the car saturday night about 30 miles and the check engine light went off. Great. Sunday afternoon i leave to go out of town and about 10 miles from my house the check engine light came on again. I have not had the code read again to see what the problem is but im sure its going to be the o2 sensor again. What is causing this problem. Im out of town for a few days and wont really be able to work on the car but its starting to make me nervous, driving around with the check engine light on. The car is the 2.4l 4cylinder with a 109,000miles on it.

Answer
No worries an O2 sensor on your car won't cause you alot of fuss, as far as driveability, but it sounds like you have a rich condition or a lean condition causing it to remain in a fixed area rather than to fluctuate voltage, causing your insufficient activity.