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Fuel Pump Won't Prime Or Run

  • Thread starter Thread starter 92hydestang
  • Start date Start date Mar 16, 2010
9

92hydestang

New Member
Mar 16, 2010
4
0
0
Atlanta area
Mar 16, 2010
#1
  • Mar 16, 2010
  • #1
This is where I am at. I have a 92 5.0 that will not start. I have put new fuel relay in hoping that would fix the problem and...nothing. I can use a wire to ground out at the test port and the fuel pump will work. I can also ground at the relay and the pump will work and start but as soon as I remove the ground the engine dies. Anybody got any ideals?

PLEASE HELP!!
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 16, 2010
#2
  • Mar 16, 2010
  • #2
Better check continuity from the relay ground to PIN 22 at the ECM. See what you get. Computer unpluged.
 
9

92hydestang

New Member
Mar 16, 2010
4
0
0
Atlanta area
Mar 16, 2010
#3
  • Mar 16, 2010
  • #3
If I get continuity...could the ECU not be letting the relay work?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 16, 2010
#4
  • Mar 16, 2010
  • #4
Pretty much it. The fact that you can manually jump the relay, says the relay is fine. And the pump works. Leaves the ECM.

If money is tight. Then I would manually ground the relay. Just until you get another ECM should that be the cause.

Often time the electrolytic capacitors inside start to go bad with age. They leak on the board. Can cause no fuel pump prime, or a constant fuel pump. But that's just one of the possibilites.
 
9

92hydestang

New Member
Mar 16, 2010
4
0
0
Atlanta area
Mar 17, 2010
#5
  • Mar 17, 2010
  • #5
I have checked the voltage at all the locations as described in another thread. I have determined that I have power in all the right places as sholud be. I will pick up a computer tomorrow. A reman unit cost $96.00. Hopefully this will get me going.
 
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