Turns out it is the connector. The insulation on the wires is all coming off. It's at 107,000 mile so it's too late for the recall, but I was able to order just the pig-tail from Autozone for like $12, so hopefully that will correct the P0171, and I built and MIL Eliminator for the PO420, and as soon as I get those cleared I'll start looking for that vaccumn leak.