I was replacing the valve cover gaskets this afternoon, and while everything was apart I stumbled on this:



It's a black wire coming out of the main engine bay harness - it looks like there was also an orange wire with at it some point, but there ain't much left of the orange part.

Any idea what it may have gone to? I'm pretty certain everything underhood is plugged in and properly connected... the car certainly starts & runs right (and passed California smog last week, even), so I'm at a loss...

There is a lot of baked wiring - partly due to age, but partly due to the fact that when I got the car the smog pump check valves were toast and disconnected, so a fair amount of hot exhaust was exiting through the hood. This is the only thing I've found that's broken beyond recognition. Everything else has been easily remedied.

Thanks for any pointers!

 

There should be a ground wire next to the thormostat housing on the intake manifold.

 

I am pretty sure that's not there, so that's a likely possibility. Thanks! Any thoughts on what that fragment of an orange wire would be left from?

I'll look at the wiring diagrams, but not knowing where it's from or what it's going to makes it hard to trace...