Stop in for a cup of coffee

Busy morning. Checkin stuff on the Neon. Had low oil pressure and #4 misfire. Disconnected battery to clear codes. It was a quart low on oil so added that. Pulled a couple wires off the coil and noticed the one on #4 was black compared to others. Like painted black. So sanded it off a bit will see if that makes any diff. Also found this wire tucked up under the harness. Looks like a filtered ground, but no idea what for and no obvious spot nearby that it would go under a bolt. ??? Will have to get wire color and see what is near it in harness so I can check schematic... I did touch it to the block while running and it didn't seem to make a difference.

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