1999 GMC Sonoma fuel pump wont prime

1999 GMC SONOMA
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HOOT712
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  • 3 POSTS
Electrical problem
1999 GMC Sonoma 4 cyl Two Wheel Drive Manual

truck cut off, fuel pump was replaced, found to be bad. Fuel pump wont prime, can jump fuel pump with spare batt. and truck will start. Switched fp relay with horn relay and horn still works. Fuses under hood and dash are good. Had to splice new harness for the fuel pump, continuity ck good on splices.
Jun 8, 2009 at 11:54 PM
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RASMATAZ
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The ECM B fuse 20amp powers the fuel pump relay and the ground for the relay is on the right side of the engine


https://images.2carpros.com/forum/automotive_pictures/12900_fp1_rELAY_1.jpg

Jun 9, 2009 at 1:19 AM
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HOOT712
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I have 12v momemterily on gray fuel pump lead, used jumper to make second ground to frame from fp ground. still nothing. will ck on the ecm gound u mentioned
ty for the help
Jun 9, 2009 at 3:41 PM
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