Mechanics

FUEL PUMP WON'T RUN

1998 Ford Explorer

Electrical problem
1998 Ford Explorer 6 cyl Four Wheel Drive Automatic 190000 miles

THe fuel pump will kick on for a split second when the key is turned on and that's it. I took it to the dealer and they said it had something in the fuel tank and it wouldn't let it build pressure but I dropped the tank and the gas is good and a new fuel pump does the same thing even before it was submersed in the gas. If I hook a hot lead to the fuel pump it will run and build 40 psi but it still won't start. This leads me to believe the injectors also aren't working. It will start and run off starting fluid. I checked all the fuses and the fuel pump relay and they are all good. I checked the cam position sensor and it seemed to be good but the book said one of the wires going to it should have 1.5 volts and neither had anything. The crank position sensor seemed to be good too. I also got a computer from the junkyard cause I thought maybe that was it but it still does the exact same thing with the different computer in it.
Avatar
Nailing
July 10, 2008.



Check the ignition switch continuity, injectors are foried when the switch is turned, if ok, check the Power relay, in the CCRM.

Merlin2021
Jul 10, 2008.
Inspect and test the PCM power relay and the inertia fuel cut off switch-

Check for power at the red wire on the injectors-No power there you're right back to the PCM power relay -it powers it -power there and no injection pulses could be the computer ground drivers-

Rasmataz
Jul 10, 2008.
The PCM relay and relay fuse are both good. There is power to the red wire to the injectors and when I probed the test light into the other wire on the injector with the key on the injector clicked and the test light lit up.

Tiny
Nailing
Jul 10, 2008.
The inertia switch is also good. When unplugged the fuel pump does not even kick on for the split second.

Tiny
Nailing
Jul 10, 2008.
Did you test the fuel pump?

Test for power at the dark green and yellow wire at the inertia switch.


http://www.2carpros.com/forum/automotive_pictures/12900_relay_13.jpg


Rasmataz
Jul 11, 2008.
Check the #3 maxi fuse in the power distribution center, under the hood, it does both the fuel pump and the anti-theft or RAP module.

Merlin2021
Jul 11, 2008.
The fuel pump is good. It does kick on for a split second. It gets power to it. I checked every single fuse on this thing and they are all good.

Tiny
Nailing
Jul 11, 2008.
Is your check engine light on? Does it work with key in on position?

Merlin2021
Jul 11, 2008.
The fuel pump is good. It does kick on for a split second. It gets power to it. I checked every single fuse on this thing and they are all good.

Did you physically checked the fuel pressure to ensure its producing the correct fuel pressure with a fuel pressure gauge this is a must-

Rasmataz
Jul 11, 2008.
http://www.2carpros.com/car_repair_video/test_fuel_injection_pressure.htm
Go here and checkout our video.
Autozone rents the tool, then refunds all your money when you return it.

Merlin2021
Jul 11, 2008.
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