I would say you need a new one yes. Middle green/lt green wire is the output. Black/white wire is the ground source to use to check it. There is adjustment on this sensor, but 2.2 at closed throttle should not even be possible to achieve at any adjustment unless your idle screw is way too high which is still doubtfully possible.
with your volt meter hooked up you should be able to open the throttle up slowly and voltage will steadily rise up to 4.6-4.8 volts at wide open throttle.
Oh, make sure there is nothing wrong with the throttlebody itself or the cable to it, just in case.