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10-17-2009, 06:29 PM
| #1 |
| Junior Member Join Date: Oct 2009
Posts: 11
 | 1991 K2500 fuel pump keeps running 1991 K2500 7.4L 14100 miles Turn switch off and fuel pump continues to run. Where to start? Thanks a lot. |
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10-17-2009, 06:56 PM
| #2 |
| Senior Member  Join Date: Oct 2005 Location: Birmingham, AL
Posts: 648
 | Check for a stuck relay
__________________  On a quiet night you can hear a Ford rust  |
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10-17-2009, 07:10 PM
| #3 |
| Junior Member Join Date: Oct 2009
Posts: 11
| pulled relay, pump kept running  |
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10-17-2009, 07:20 PM
| #4 |
| Senior Member Join Date: Oct 2005 Location: Birmingham, AL
Posts: 648
| check your wiring, ignition switch, and all grounds. I have seen bad grounds do strabge things
__________________ On a quiet night you can hear a Ford rust |
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10-17-2009, 08:22 PM
| #5 |
| Senior Member  Join Date: Mar 2008 Location: N.Y.
Posts: 4,300
| start looking for a short between 2 hot wires, 1 being the fuel pump ower and something else
__________________ 4 wheels move the body 2 wheels move the soul B.W.A.I |
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10-17-2009, 10:44 PM
| #6 |
| Senior Member  Join Date: Jul 2009 Location: Fredericksburg, VA
Posts: 1,906
| And check the oil pressure switch.
__________________ If the guys who design 'em had to take one home, use it every day for 2 years, and do all the maint and repairs themselves, cars would have a button on the dash to change the oil, filters & plugs. |
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10-17-2009, 11:03 PM
| #7 | |
| Junior Member Join Date: Oct 2009
Posts: 11
| Quote:
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10-17-2009, 11:22 PM
| #8 |
| Senior Member Join Date: Jul 2009 Location: Fredericksburg, VA
Posts: 1,906
| The oil pressure switch is part of the fuel pump circuit. It's setup that way to prevent the fuel pump from running if oil pressure drops to zero. Sort of a safety circuit. If the switch shorts though it can cause the fuel pump to run, even with the ignition off.
__________________ If the guys who design 'em had to take one home, use it every day for 2 years, and do all the maint and repairs themselves, cars would have a button on the dash to change the oil, filters & plugs. |
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10-17-2009, 11:39 PM
| #9 |
| Junior Member Join Date: Oct 2009
Posts: 11
| O.K. Thanks, will be checking that tomm. |
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10-18-2009, 06:10 AM
| #10 | |
| Senior Member  Join Date: Jul 2007 Location: on your 9
Posts: 3,366
| Welcome to the forum warmullins. Quote:
 Believe on the 91 you can add another suspect, same type of fault. If unplugging the oil press sw does not get it, look to the Fuel Module. I seem to recall leo reminding me about that almost a year ago.  Yanking the Gauge fuse may give quick results for info. DO NOT do that for the oil press by pulling the ECM fuse because messes with codes/memory. .  | |
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