1990 ford bronco

help please my truck will turn over but will not start. I have noticed the fuel pump will cut on and will not cut off. fooling around with it I have
noticed that sometimes even when I turn the key off the pump will still run. no matter how long I keep the key on the pump will not cut off any help would be appriciated.
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Do not know if it will be the same or not but.........We have a 88 Bronco. Was told that it has 2 fuel pumps. One in the tank and the other is on the frame like just in front of the driver door. Have had it do strange things because of loose wire on fuel pump and have fixed other probs by changing the fuel filter also near the fuel pump. Also could have something to do with your key switch. We had to put a toggel just under the dash to start ours with. Still have to have the key in it and turned on before you push the switch to turn it over but was alot cheaper than haven the colum torn apart. Kinda makes it to be a anti-theft feature...... If you don't know it is there you dont start it . Any way a few thing to check. Hope it helps.....
shadetree78 wrote:

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Ignition switch (the actual electronic switch, not the metal key switch that you put the key into). Or, you may also want to check the fuel pump relay under the hood. Should be near the distribution block, if your truck has one.
Sharky
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It's not unheard-of for either the PCM or Fuel Pump relay contacts to fuse together. I've heard that the PCM relay has to engage before the Fuel Pump relay will. If that's true, then perhaps you're a rare case in which both PCM and Fuel Pump relays are stuck "closed."
CJB

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Just to add to CJB's post, and to reiterate on my own earlier post, the fuel pump and EEC (aka PCM), on the older Bronco IIs, Rangers, full-size and a few other Ford vehicles, are documented to be troublesome. There is actually a TSB on the failure of Ranger fuel pump and EEC relays, which causes the battery to slowly drain overnight (went through this gremlin myself with my 1991 Ranger). It does not explain in detail what actually happens, but I would imagine that after numerous years of driving, the contacts inside the relay slowly wear themselves out to the point where they eventually 'stick' together, which causes a slow, continous drain on the battery. In the case of my own truck, both relays are identical, so one would assume they would naturally fail around the same time.
Good luck and I hope you can figure out what is at fault. Sharky
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