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1995 Chevy 4x4 not getting power to pump

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Old August 17th, 2018, 2:53 PM
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Default 1995 Chevy 4x4 not getting power to pump

My truck has been sitting in a garage for almost 4 years. It is a 1995 rare 5 speed manual long bed, 5.7 TBI. My wife bought Duramax z71 so I garaged the 95. I figured that she would get tired of the Duramax and sell it. She hasn't. Almost all the gas was out of the 95 when I stored it, but I also added stabilizer before I stored it. I decided to sell it because I am just too old to hunt out of it anymore. All my hunting buddies are dead or taking care of their grandkids. I no longer go to the woods by myself. So, I am going to sell the 95. I tried to get it ready to sell after adding 10 gal of new gas and charged a new battery. It would crank over but not ignite. It will ignite via starter fluid or gas added directly to TB. Fuel pump relay and fuse tested to "specs." However, multimeter and 12 vt test light indicates that fuel pump is not getting power at the pump's quick connector. So, it is not pumping gas. Unless rats ate the wires into that feed the fuel pump, I don't have any idea what could be causing voltage not to reach pump. Any suggestions would be appreciated.
Old August 17th, 2018, 3:28 PM
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You can check continuity from the pin on the connector to the relay contact base. That will indicate if the wire has been chewed. I would if it were my truck, jump battery voltage to the pump while trying to start it, that would eliminate alot, then you can isolate why no power.
Old August 17th, 2018, 5:44 PM
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Originally Posted by kevinkpk
You can check continuity from the pin on the connector to the relay contact base. That will indicate if the wire has been chewed. I would if it were my truck, jump battery voltage to the pump while trying to start it, that would eliminate alot, then you can isolate why no power.
Thanks for replying. Best we can tell, no voltage at pin connection. It was hell moving "dead" truck out of garage. Rotors and drums were rusted up a bit. We had to move around a lot of junk before moving it. . We might have missed something in all the confusion. Truck is outside now with plenty of room to work around and underneath. I have a lot of 12 and 14 gauge wire that I was planning on doing what u recommended. If pump energizes, then I suspect the real work will begin to find where the rats ate my wires. Again, Thx!
Old August 17th, 2018, 6:34 PM
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If that is the case, rats eating wire, I'd recommend finding the connectors, and rewiring that
Old August 17th, 2018, 9:47 PM
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Originally Posted by kevinkpk
If that is the case, rats eating wire, I'd recommend finding the connectors, and rewiring that
I friend indicated that there is a wire to oil pressure switch that may cause issues too. A safety issue...
Old August 18th, 2018, 12:14 AM
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When you 1st turn key to on position do you hear the fuel pump run? My 93 had your symptoms - ran with gas poured in throttle body - needed a new ICM in the distributor
Old August 18th, 2018, 8:27 AM
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Originally Posted by Rednucleus
When you 1st turn key to on position do you hear the fuel pump run? My 93 had your symptoms - ran with gas poured in throttle body - needed a new ICM in the distributor
Pump never runs when key is turned on. Since pump quick connector is a three pin design, and there is a lot of undercoating sprayed underneath including the wiring, it is difficult to determine the positive feed into connector. In addition, I am sure one of the pins is for ground. My Chilton manual is not real clear if oil pressure switch may be causing electrical issues. I do know that some vehicles use a special oil pressure switch to stop fuel pumping should engine "die"." However, my model may rely on computer to sense motor not running and will issue command to stop pump. THX!
Old August 23rd, 2018, 10:47 AM
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We have isolated power getting through "keyed" tri-connector quick disconnection at fuel pump but pump is not pumping, vibrating, etc. Is pump grounded via the tri-connector or through being connected to metal tank and tank is supposedly grounded? If my memory is correct, fuel pump is connected to tank via a cam like seal. This seal would prohibit pump being grounded. Hence, the grounding is via plug. Before I pull tank in order to access fuel pump, I'd like to know whether or not grounding is via plug.




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