No power to the fuel pump

Tiny
ANTNYLEE
  • MEMBER
  • 1991 FORD F-150
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 250,000 MILES
I have replaced the fuel pump relay, fuel pump, fuel filter and there is still no power to the fuel pump connector. This all happened one day after I replaced the spark plugs and wires. Everything was running fine before that.
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Sunday, January 10th, 2010 AT 7:00 PM

29 Replies

Tiny
RASMATAZ
  • MEMBER
Check and test the inertia fuel cut off switch could be tripped or bypass it and see if the pump come On.
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Sunday, January 10th, 2010 AT 8:24 PM
Tiny
RONNIEJD
  • MEMBER
  • 1991 FORD F-150
  • V8
  • 2WD
  • AUTOMATIC
  • 210,000 MILES
91 F150 fuel pumps won't turn on. Have changed the fuel pump relay, eec relay, fuse, and inersha switch with no luck. Any suggestions.
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
KHLOW2008
  • EXPERT
Have you tested for power supply to the relays?
Apart from parts replacement, what have you tested?
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
RONNIEJD
  • MEMBER
Have checked fire to eec relay, fuel pump relay, and fuel pump fuse all have fire. Checked fire at selector switch, one prong with low voltage. Inersha switch not triped.
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
RONNIEJD
  • MEMBER
Have tested both relay sockets, and they have fire. Checked the fuse socket, and it has fire. Checked selector switch which has low voltage on one terminal. Inersha switch not tripped.
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
RAYGOCH
  • MEMBER
  • 1991 FORD F-150
  • 6 CYL
  • 4WD
  • MANUAL
  • 130,000 MILES
When you turn on key without starting fuel pump will not shut off. Will not start until you shoot ether into air intake. Replaced coil and module on distributor and fuel pump and fuel pump relay. Once running cannot gun engine you have to feather accelerator to rev up. Would pick up coil or pip sensor in distributor cause fuel pump to continue running and the starting issue or something in the fuel system. I do not know where to begin.
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
BMRFIXIT
  • EXPERT
Need a fuel gauge and check what do you have for fuel pressure

do you have 2 tanks or one
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
KHLOW2008
  • EXPERT
At the self test output connector, does grounding the Light Blue/Orange wire works the fuel pump with ignition on?
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
RAYGOCH
  • MEMBER
Have dual tanks and have about 50 lbs on fuel pressure.
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
CADIEMAN
  • MEMBER
Take the fuel pump pressure with a gauge. Also check the injector fuse.
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
BMRFIXIT
  • EXPERT
Check TPS sensor
(check volts at idle and wide open throttle also do a wave test )

check injector pulse
check exhaust flow
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
RONNIEJD
  • MEMBER
Stuck screwdriver in self test connector on the light blue/orange wire and before I grounded it the pump started working. Does that mean a wire was loose in the self test output connector and should I change the self test output connector. Seems to be doing great now. Thanks for all your info and help.
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
JONZEY1253
  • MEMBER
  • 1991 FORD F-150
  • 6 CYL
  • 2WD
  • MANUAL
  • 98,000 MILES
I have 1 91 F150 with dual gas tanks. When I turn the key to the on position I hear the fuel pump prime like it should, the only problem is that it does not turn off after a few seconds like it should. When I switch back and forth between tanks I can hear it switching fuel pumps, but whichever one is selected runs continuously. The truck will still start, but it runs very rough and dies quickly unless I keep my foot on the gas. The check engine light is on but I have not wanted to risk messing something up by driving it somewhere to be looked at. I replaced the fuel pump relay, needless to say, that did not fix the problem. What should I do?
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Thursday, July 18th, 2019 AT 10:17 AM (Merged)
Tiny
MERLIN2021
  • EXPERT
Fuel pump should run for 2-3 seconds with key in on possition, after it starts, it will continuosly run until shut off, but if it keeps running A.) after key is off, or for more than 2-3 seconds with key on, the fuel pump relay is no good(stuck). As you have changed it already then lets read the codes. here's how to do it by counting the blinks of the MIL(check engine light. Do this and count the flashes...Count the flashes, a 22 will flash as 2 flashes then a short pause, then 2 flashes, if more than one code is stored, the pause will be longer. The codes will display three times and end with 11 or 111. Write them down and post here. First do this with the key on engine off, then again with it running.


http://www.2carpros.com/forum/automotive_pictures/62217_Pre_95_Ford_8.jpg

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Thursday, July 18th, 2019 AT 10:18 AM (Merged)
Tiny
KHLOW2008
  • EXPERT
That seems odd. The self test connector is connected to the fuel pump relay and ECM fuel pump grounding circuit. The only possibility for the problem would be a bad connection for the Light Blue/Orange wire which also leads to the ECM from there.

From back of self test connector, check the connection of the 2 Light Blue/Orange wires. It is not necessary to replace the connector, repairing their continuity should solve the problem.
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Thursday, July 18th, 2019 AT 10:18 AM (Merged)
Tiny
RAYRAY118
  • MEMBER
What was the answer to your problem my 91 is doing the same thing. Fuel pump in always truck will not start but has fuel and spark
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Thursday, July 18th, 2019 AT 10:18 AM (Merged)
Tiny
RONNIEJD
  • MEMBER
Truck started twice after it first started up. Test drove it about 3 miles. Turned it of. Now it won't start again. Tried to ground self test output connector. Nothing but fuel pump relay clicks and eec relay gets warm to touch.
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Thursday, July 18th, 2019 AT 10:18 AM (Merged)
Tiny
DANNY L
  • EXPERT
Sorry.
You've attached a question to one that is years old.You need to start a new question with your vehicle information.Thanks for using 2CarPros.Here's the link.
Danny-

https://www.2carpros.com/questions/new
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Thursday, July 18th, 2019 AT 10:18 AM (Merged)
Tiny
CADIEMAN
  • MEMBER
Ck the pump pressure!
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Thursday, July 18th, 2019 AT 10:18 AM (Merged)
Tiny
KHLOW2008
  • EXPERT
After grounding the Self test connector, test for battery voltage at the fuel pump. If voltage is available, check the fuel pump grounding circuit.
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Thursday, July 18th, 2019 AT 10:18 AM (Merged)

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