I have the FAST wideband o2 sensor for E85 with duel O2 sensors and am trying to get a reading with open headers. I know it should not/will not work at all at an idle but can not get it to work at WOT either. The readings just jumble around with no rhyme or reason. My bungs are 6 inches from the ends. will extensions make a difference? I had the same problem with my old headers with 16 inches of pipe after the bungs/sensors. Is my sensor bad or is this just not a good idea for open headers?