Just finished putting my buddys 94 850 turbo back together after cleaning out the intercooler and hoses. When I got to the relays above the radiator the plug for the fuel injection relay only had two of the four wires in it.The green wire and the orange & blue wire were still in place but the two red wires were hanging loose. Does anyone know where I can find a diagram to figure this out.

 

check out two online resources:

volvotips.com

volvowiringdiagrams.com

 

Also, there is a guy who makes those pieces that go bad. There may be other places to buy them, but this is the only one I know of. these might be volvo parts, I don't know.
http://www.davebarton.com

Look on the Harness Parts page about a third of the way down.

I don't "fix" them right myself, I just redneck stuff together using standard round plugs until electricity flows.