Where's this wire go?, and other useless info Options

[deserttoad]

Working on a 1975 1.8 with FI.

So I need to know where the wire that comes up through the tinwork with the throttle cable goes. It's hard to see, but I believe it is green. So I'm thinking it must be for the temp sensor? It is just a bare metal spade, and I don't know where to plug it in. Or does it perhaps go back to the dash to my oil temp gauge (hasn't ever worked)? There is no other obvious unplugged wire around.

And don't I see a temp sensor right on top of the motor as well - is that the one for the computer to use?

And speaking of electrical things - my tach only works at low revs all of a sudden, and my amp meter and fuel gauge have quit as well - what gives, is there a common ground?

thanks,

DT