There will be a Factory Splice for the frame rail fuel pump.
Odd about the yellow wire though?
Do you know where your inertia switch is?
Passenger footwell just above carpet under glove box usually.
That is where the fuel pumps power wire connects.
There should be a Pink wire connected there, that runs over to drivers side and thru the floor, it goes to the pump in the tank, that "yellow wire" should have been spliced to that pink wire.
Reason the yellow wire is an odd color for them to use there is that the Fuel Gauge wire is also Yellow with a white stripe and it is in the same harness going to the gas tank
But look at the inertia switch to see the wire colors as I do not have an 1986 wiring diagram.
Dark Green wire comes from the fuel pump fuse(vial fuel pump relay) and Pink wire goes out to pump
Last edited by RonD; 05-14-2016 at 09:02 PM.