While prowling around the back of the engine chasing down my P0171 nemesis, I stumbled upon a loose connector. At first I thought I had knocked it loose, which is scary when you can't find the other end! It's a two wire, female connector with black & Red/white wires.

My schematic shows something called an "Ignition Coil Relay" that was installed on earlier cars. It's the only thing I can find with those color wires. Did they leave that pig-tail and connector in cars that no longer had that relay? Here are some pics:

BTW: For those of you with Super Chargers, there is a 2 inch vacuum hose that goes from the throttle body elbow (base) to the Bypass Actuator at the left rear of the engine. Mine was a thin walled, fairly stiff tube, which was almost completely collapsed. I replaced it with more routine rubber vacuum hose.

 

It is not used on mine and is just taped out of the way.

 

Perfect. That confirms it. Thanks Chris!