2.8l Please help with unknown wires.
 

The wires are black and tan. They are coming out of the largest harness in the behind the distributor. They are pinched between the block and the transmission. I did not build this so I'm trying to figure out whats up. The engine is a rebuild and it runs like crap. Sorry if this is posted in the wrong area.

I've gotten the engine running. I took off the dust cover and looked up and saw the brown wire and black wire were joined to a loop connector. I figured this was suppose to be grounded. The engine is running and that is all I'm concerned about now. If you know why these wires would be put together for a ground please let me know.