hardwiring a fuel pump

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Mar 30, 2009 | 03:55 PM

colorsink

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hardwiring a fuel pump

hi i have a 90 f150 4.9 what wires would i hook up to a switch to activate the fuel pump for testing purposes

Mar 30, 2009 | 04:02 PM

RIKIL

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I am taking a guess here but this might get you started...

Sounds like you have only a single tank. On your instrument panel, just to the right of your headlight on/off switch, you should have a blank spot in the plastic. Behind that blank spot are some wires relating to your fuel pump. This is the spot where a front/rear switch is normally put. If you take off the plastic for the instrument panel, which takes less than 10 min, and supply power there, it might get you what you need. I think that is what I used on my 92 F150 to power it on.

Mar 30, 2009 | 04:03 PM

1966Tbird

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there is an enertia switch to the right of the big plug that goes into the firewall behind the brake pedal, the lighter color wire goes to the enertia switch then the darker wire goes to the pumps

Mar 30, 2009 | 06:51 PM

colorsink

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so if i wire it from the inertia switch will this bypass the relay?

Mar 30, 2009 | 06:54 PM

subford

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From: Easton,Ks

Quote:

Originally Posted by colorsink

so if i wire it from the inertia switch will this bypass the relay?

Yes it would.

Mar 30, 2009 | 09:27 PM

EPNCSU2006

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From: Concord, NC

You can also manually force the relay to energize by jumpering the fuel pump wire to the signal return wire in the diagnostic connector under the hood.