Do any of you know what this harness is for, called (so I can try to look it up), what should plug into it? Maybe this one doesn't connect at all-could be from something someone changed long ago. This is on a 1990 Camaro RS. The harness is below the dash, driver side, above the clutch pedal , to the right of the fuse block-to the left of the steering column & hi/low selector. Thank you.

 

Nothing plugs into that , that is your "diagnostic connector" (OBD1 connector) and is used to read the codes from the ECM during troubleshooting ..

 

Thank you. Do you know if I leave this "post/tread" open or how I take care of it now that there is an answer?

 

There is no open or closed. It'll just sit here.