GMC SERRIA

HALLWILLIAM 72

MEMBER
1991 GMC SIERRA
V8
4WD
AUTOMATIC
220,000 MILES

91Gmc Serria has no fuel and no fire power to the fuel pump with the key in the on position but no power to the the pump in the start position no fire at any time. Replace the ecm, fuel pump, fuel pump relay, ingnition switch, oil pressure switch

Monday, January 17th, 2011 AT 4:39 PM

6 Replies

JDL

MECHANIC
16,098 POSTS

Did you check the inline fuse? Should be close to fuel pump relay.

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Monday, January 17th, 2011 AT 4:54 PM

HALLWILLIAM 72

MEMBER
2 POSTS

Yes checked the inline fuse with a test light it has power to the fuel pump in the on position for 2 sec and then goes out but in the start position no power to the fuel pump and there is no spark coming from the distributor or coil

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Monday, January 17th, 2011 AT 5:26 PM

JDL

MECHANIC
16,098 POSTS

In the diagram, check gray fusible link. That is hot all the time. Supplies voltage to both the o/p switch and the load side of fuel pump relay.

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Monday, January 17th, 2011 AT 6:04 PM

JDL

MECHANIC
16,098 POSTS

The fusible link should be at the battery junction box on the firewall.

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Monday, January 17th, 2011 AT 6:09 PM

FORD MAN

MEMBER
115 POSTS

It might be something as simple as bad/no grounds between body & motor,
or something as difficult as finding bad/broken wires. Happy Hunting !

Ford Man in Michigan