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Discussion Starter #1
Ok I am getting no power coming out of the cylinoid for my fuel pumps on my truck. I have a 1988 F150 4x4 with a 351w and a C6 tranny with duel tanks. I replaced both tank pumps and the inline high volume pump. replaced the cylinoid, and the computer. I turn the key and the truck turns over but I have no power to the fuel pumps ( never hear them kick on ) can someone help quick please. the repair book said the yellow wire into the cylinoid is what sends power the the pumps and to check that for damage. the red wire is constant power and the brown wire goes to my tank selector switch and inerta switch. PLEASE HELP ME
 

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green ones make me horny
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kibblepup83 said:
ya steve thanks alot. hows that sapose to help me get my truck started

well that is no way to talk to people is it? he was saying dont double post. as in it doesnt help your cause.

have you checked for actual power in the two wires? if not why havent you? you need to diagnose a problem instead of throwing parts at it hoping that it will go away or get better
 

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Yeeeeehaw Y'all!
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Have you checked the fuel pump relay?

On a Bronco.... (at least on my 88) it's one of the two relays on the drivers side fender well.
 

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kibblepup83 said:
ya steve thanks alot. hows that sapose to help me get my truck started
Steve probably would have solved your problem by now without that comment :twak Anyhow, I would suggest getting a cheap voltmeter from radio shack or wherever. Unless you just want to keep throwing money away, your going to have to do a little troubleshooting since you do not have power to the pumps. Once you have a meter, we can help point you in the right direction. Problems could range from eec relay, fuel pump relay, fuses, fusible links at the starter relay, inertia switch, ect.
 

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kibblepup83 said:
Ok I am getting no power coming out of the cylinoid for my fuel pumps on my truck. I have a 1988 F150 4x4 with a 351w and a C6 tranny with duel tanks. I replaced both tank pumps and the inline high volume pump. replaced the cylinoid, and the computer. I turn the key and the truck turns over but I have no power to the fuel pumps ( never hear them kick on ) can someone help quick please. the repair book said the yellow wire into the cylinoid is what sends power the the pumps and to check that for damage. the red wire is constant power and the brown wire goes to my tank selector switch and inerta switch. PLEASE HELP ME
The yellow wire does not send power to the pumps. Power comes to the Inertia switch on the Brown wire and exits the switch on the Pink with Black stripe wire. It then has a splice that splits the circuit, Pink with black to the High pressure pump and red with white stripe to the Fuel tank selector. From the fuel tank selector switch it goes on a Red wire to the front tank and on a brown with white stripe wire to the rear thank.

If you get no power to either pump (check it with a multimeter for 12V) check the "in" and "out" of the inertia switch. They have been known to fail.

Going back from the inertia switch on the brown wire you go to the fuel pump relay via connector C100. The Fuel pump reay is powered by the pick of the EEC Relay a red wire and back thru the EEC Relay contact to the Yellow wire and back via a fusable link to the start Relay on the Battery side.

So someplace along that rambeling route your power path is broken. Use a multimeter to check it out rather than throwing parts at it.

Hope that helps you.

:thumbup
 

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Discussion Starter #7
the problem is the yellow wire that comes into the fuel pump relay is getting constant power all the time. the wireing diagram shows it should olny have power when the ignition is on. I checked all the fuseable links and they are all good. and the reason I replaced the intank pumps is cause the rear tank never worked since I got it and i figured for a little extra money i might as well put a new one in the front tank to be safe. I changed the relays cause they are like $5 at the auto parts store and thats what everyone told me to do first. I changed the computer cause thats what the local shop and dealership told me was wrong. so now im stuck and need some more help. it turns over great just the relay does not click and the pumps dont come on unless i cross the circut with a jumper. but then the ppumps run constant.
 
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