I am having a problem with locating the root to this problem.bank 2 seems to be 8% higher than bank 1 on the kamrf's. I do not find a exhaust leak any where. Have looked for vacum leaks have not found one. I put two new o2's in since they were old and one was switching slow. New plugs,cap,rotor, and compresssion test was with in 2%. Does anyone have a suggestion on what else to look for.