My car has been acting up lately. It seems to be losing power around 2300-3000 rpms when i am at half throttle. But at full throttle it does not seem to lose any power. Then sometimes it will lose power big time and i cant even give it gas or it will be too jerky. But sometimes it will run great. I checked to codes and it came back with P0141 O2 sensor circuit heater malfunction bank1 sensor2. Is that what is causing my car to act up? Also how do i know which O2 sensor that is? Hope someone knows whats going on.