While working on some general maintenance under the hood of my 84 DL, including patching some flakey sensor wiring, I fealt the need to remove...or rather unbolt and hang aside the intake manifold since i can't seem to get it off without cutting the main harness. Definately missing something here??

Anyway, while repairing the toasted knock sensor wire and lamenting at where to find a temp sensor locally that literally sheared off when unplugging the connector, I noticed a single blue wire that i didn't recall seeing before with a blue ID tag of some kind dressed in black plastic loom going back into the main harness. it has a single OEM looking uninsulated female spade connector and for the life of me can't figure out where it attaches since all the main sensors are accounted for (I think). I even have a reserve 83/84 harness at the ready for that inevitable day and i don't see this single blue wire anywhere on that backup harness. The shape of this span of blue wire is rather straight and about a foot in length coming out of the main bundle leading me to believe that maybe it attaches to a vacant male spade connection on the solenoid which looks somewhat shiney and not grimy, but i can't find a reference for it at the starter location in the volvo wiring diagrams for 84. I have all the required wiring there and so am reluctant to just attach it to that post. Coincidentally, the 84 LH2 diagram does show a blue and black wire going to the temp sensor from the ECU, but like i said, that sensor is accounted for with a DOUBLE insulated connector.

Hoping someone out there can chime in on this by Monday, otherwise both me and my blue friend will both be left hangin after my volvo is buttoned up again. thanks.