there is only one bank on these, there are two o2 sensors- one on the rear manifold(the one critical to how these run and there is one after the cat. to make sure the cat is running right. Do you have a check engine light on? If so get it scanned and let us know the actual code number from it. If not, does it idle normally? Does it only feel slow under acceleration? any certain rpm range? all gears? When was the last time you checked your air filter to see if it was clean? Is it stock? When were the last time the plugs and wires were changed? What plugs do you have in it? We need more information and be specific.
