Fuel pump voltage

[Golden76]

Hey everyone, new here but I've had my ranger for about twelve years now.
So I have 12 volts going to the fuel pump relay, but I only have 6.8 volts to the inertia switch and down to the fuel pump? This doesn't seem right to me. Also the wiring on the prints to the inertia switch and EEC call out org/lt blu but the one going to the switch is a gr/yl. Both wires from the relay are gr/yl but seem to be going to ground.
Everything else is correct, but I'm stumped. Hard starting and erratic idling. Also having issues with fuel gage which I am still digging into.

 

[franklin2]

Here's a diagram that has darkgreen/yellow wires going to the relay.

Red is the hot wire from the EEC relay. This wire is hot anytime the key is in run and start. It goes to the coil of the relay.

The coil is not grounded. The coil gets 12v from the red wire, but the relay will not activate until the computer grounds the lightblue/orange to activate the relay.

The black/yellow is hot at all times. It sits there and waits for the relay to activate. Once the computer activates the relay, 12v goes down the darkgreen/yellow to the inertia switch and then out to feed the fuel pump. The darkgreen/yellow branch circuit that goes to the computer is just for the computer to monitor the voltage to the fuel pump.

You can also see another branch on the lightblue/orange computer control wire. This leads to the code test plug where you can manually ground this wire and activate the fuel pump relay for testing. Handy for what you are doing right now.

 

[Golden76]

Thank you for the information and the better diagram, this will help alot.
In all I should be getting 12v all the way to pump and the green/yellow should not be ohming to ground with the key off and no relay or inertia switch connected?

 

[franklin2]

You may get a reading through that computer input, I do not know. If you had a short to ground, you would think you would have melted wires or burnt fusible links.

Correction. Blown 30 amp fuse.

 

[bobbywalter]

11.5 ish or hopefully better with those old arse wires.