[BlueDragonVT]

Ok, here's the story. My girlfriend's 2005 Ford Police Interceptor has a check engine light on. We pulled the codes to see what we could do. She had a couple codes that were easily fixed by replacing the gas cap. She also had a couple of O2 sensor codes, including a P0161. We replaced the gas cap and O2 B1S2 and checked it, but we were still getting a P0161. We ran live data on the car and found that B2S2 was reading a stable 0.7xx with an occasional jump to 0.8xx, instead of constantly changing like the other three. We went back under the car and pulled B2S2. Since the code P0161 was supposed to be about the heating element, we also used a volt meter to check and make sure that the elemnt was getting power, and we read 11.5 volts, so that looked good. We swapped in a new O2 sensor. We now have new O2 sensors on both B1S2 and B2S2. We clear the codes and try again, and find that the P0161 code is still popping up, and now the live data shows B2S2 stuck at 0.000, with the occasional jump to 0.005. Still pretty stable, and not changing like the other 3 readings. At this point, I am all out of ideas. Can someone help me diagnose this issue, and how to fix it? She has to reregister her car this month, and that means passing an emissions test. Any help would be greatly appreciated. Thanks, all, and happy holidays!