89bronco xlt fuel pump circuit problem

[justseggy]

Well while driving home from work one day my bronco abruptly decided to stop running. After having it towed home , I found that it was not getting fuel, and when I turned the key i could not hear the fuel pump kicking in. So I bought a fuel pump assembly, dropped the tank and, installed it. Sure enough the old fuel pump was junk. Now with the working fuel pump in tank I turn the key and i still don't hear it kick in, So i replace the relay, and check the inertia switch ,they too seem to be fine. I was wondering if you could perhaps shed some light on my situation.

-THX

 

[Seabronc]

The best thing to do is to get a volt meter and check for 12 volts at each point along the way. Since you alredy know where to find the inertia switch, start there and make sure you have 12 volts at each contact. dIf yes move toward the fuel pump, if no go in the other direction. If you have 12 volts only on one contact the inertia switch is bad. The pick for the pump relay is thru the EEC relay. Power for the pick and fuel pump comes thru fuses in the engine compartment fuse box. I don't have a diagram for the 89, but in a 92 they are 20 amp fuses I and O.

Good luck,

>-

 

[mbtech2003]

if i remember corectly and correct me if i'm wrong there should be about 8 volts at the fuel pump when running. a breef serg of 12 volts to get the fuel moving and then the 8 volts to keep it running. might be different for the 95 bronc that i have but i remember my brothers 88 5.0 mustang gt having a simmilar set up to mine /emoticons/[email protected] 2x" width="20" height="20" />

 

[Seabronc]

if i remember corectly  and correct me if i'm wrong there should be about 8 volts at the fuel pump when running.  a breef serg of 12 volts to get the fuel moving and then the 8 volts to keep it running.  might be different for the 95 bronc that i have but i remember my brothers 88 5.0 mustang gt having a simmilar set up to mine /emoticons/[email protected] 2x" width="20" height="20" />

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I suspect most fords have the same arrangement. They don't do much reinventing the wheel and if something works they usually use it on most models. However, I can't see any reason for the voltage to be less than 12 volts since there is nothing in the path from the battery to the pump that would reduce it with the exception of possible poor connections. If the engine is not running the voltage will depend on how charged the battery is.

>-

 

[American Rebel]

Try this:

Ground the fuel pump circuit of the Diagnostic Link Connector(DLC), if the pump runs, then your computer is bad.

The same thing happened to me, but I caused it... I had a exposed power wire touch the frame rail and sent the volts up through the ground wire of the High Pressure Fuel Pump and into the computer. Fried the computer... oooppss...

I think the fuel pump circuit on an EEC-IV Module DLC is the one closest to the fender, ground it, it energizes the fuel pump manually.

The DLC is located in front of the airbox, flip it over, then ground the one closest to the fender.

I'll look it up, but I'm pretty sure that's the right Connection....

Good Luck, and I hope that helps