Check these downstream sensor 2 readings,,,,which one is good and bad? The yellow and the blue are the ones Im watching : yellow is front downstream and blue is rear downstream. Both are brand new aftermarket. Then I replaced both downstreams with OEM used NTK's and I got the 2nd graph. Im not sure if this is where its supposed to be or not but they are both pretty much in unison reading wise. The upstream are still the 2 new ones (I bought 4 in a set) and I believe they are reporting properly. BTW I keep throwing a bank 2 lean condition and a bank 2 Sensor 2 heater circuit slow responding. Could I possibly have a bad bank 2 fuel injector? Im thinking the lean condition may be sensing a plugged injector as in its sensing too much 02 that was not consumed by fuel? There are no leaks and van runs fine. Wife says it idles a little rough but I dont feel it. This all started when I got a lean B2 condition and started replacing O2 sensors. Perhaps Im chasing the wrong rabbit in the o2? ST fuel trims are almost identical between banks, thats whats throwing me. ie. how could an OBD2 even be lean as its controlled so tightly by the ECU. What should fuel pressure be while idling?

 

this is a 2012 3.6 VVT FFV on E80 at the moment.

 

Lets start with what's the actual issue you have what was the original concern?