I got a rough idle so I'm trying to figure out whats going on. There is no mil light or dtc's. Im using a genisys to read some of the parameters. As the car begins to warm up, i notice b1s1 reads zero for a minute before it starts to climb and b2s1 climbs normal from the start. Once closed loop is obtained, both b1s1 and b2s1 flucuate like normal but b1s2 and b2s2 stay pretty much around .800mv. Does this sound normal?

 

B1S1 maybe on it's way out......both rear sensors are there for cat effiecency monitoring, they have nothing to do with fueling

 

that happened to me as well. on the front sensors. 02 simms in rear.