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Fuel System Wiring issue

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Old Yesterday | 11:07 AM
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Fuel System Wiring issue

I recently bought a 1988 Forumla that has been sitting for 18 years due to fuel pump failure. I put in a new tank, sending unit and pump, and filter. I jumped from the battery to the grey wire on the fuel pump relay connector and fuel came out of the line so I know the pump works. I replaced the fuel pump relay and connector. The green wire was missing insulation at the connector. If I hook a meter up to the connector I am not getting any voltage from the first orange lead or second orange lead with the ignition in the on position. I also tested power at fuse number 2 by the battery but there is no power there also. From what I read the first and second orange wires should have power at all times with the key on. The green/white wire should have power for a few seconds when you turn the switch on to prime the pump. The black wire is ground and the grey wire is the wire that powers the pump. The battery cables were changed at some point to top mount. There is a yellow crimp on connector off of the positive that is not connected to anything can't seem to find out why it is there. Where does #2 fuse get its power and does it send power to the relay?
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Old Yesterday | 04:22 PM
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Re: Fuel System Wiring issue

The large orange wire should have +12V all the time, regardless of the ignition switch. The 20A fuse near the battery is the only thing to interrupt that.



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Old Yesterday | 04:50 PM
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Re: Fuel System Wiring issue

Thanks for the reply. I’m assuming that if I trace the red wire at the fuse it should be hooked up to the battery somehow.
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Old Yesterday | 07:02 PM
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Re: Fuel System Wiring issue

I traced the red wire to a molded connector on the batter cable. Did a continuity test and the wire was broken. Spliced it to another wire and she started right up after 18 years of sitting. Thanks Vader!,
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