Thanks. Since it has 12 Volts I don't think it would be a sensor so I'm leaning towards, it's not being used.
As far as the P0171, thanks for the tips. I believe I found the issue. It's the large tube (vacuum) going into the back of the intake manifold pleum. We got a new one and I forgot to put the O-ring on the connector. Therefore you could actually hear the leak. So I went and got an O-ring that kinda-sort fit. I believe the ones that came with it are probably in a landfill somewhere.
Thanks for your help.