fuel pump relay?

2004 CHEVROLET SILVERADO
120,000 MILES
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PHILLCOMBS
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My truck has the 4.3 engine. It just quit running all at once. I thought it was the the fuel pump, so I changed it and nothing. I tested my old pump and it was working fine. I then traced all my wires up to the fuse box under the hood and nothing, my fuel pump relay? and checked all fuses and still nothing. I checked the fuel pump plug in. And it was not getting any power. What could possibly be causing this?
May 26, 2013 at 11:17 AM
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ASEMASTER6371
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Here is a guide to help check the relay and the relay location in the diagrams below.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.
May 26, 2013 at 11:28 AM
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PHILLCOMBS
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I tested all fuses with a meter. U can hear the relay kicking in and out when turning the key on and off
May 26, 2013 at 12:05 PM
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PHILLCOMBS
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I also took the cap off of the relay and u could watch it kick in and out
May 26, 2013 at 12:06 PM
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EGIANNONI
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not getting power to connector on my fuel pump. i check pump its good, i checked relay and good, checked all fuse and good. it quit on me yesturday and i notices the grey and purple wire were curoded threw so rejoined them and no power to pump, 2001 silverado 4.8
Jul 7, 2020 at 1:47 PM (Merged)
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JDL
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Engine cranking, do you have spark at the spark plugs? Do you have injector pulse? Any fuse you check, you have to check for voltage on the fuse circuit. Use a voltage tester. Wiring diagram below.
Jul 7, 2020 at 1:47 PM (Merged)
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WALKERSTIRE
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i have changed , fuel pump,rotor,cap,plugs,wires & i still have a intermidant miss in the motor. the reason i changed fuel pump is my pump relay get very hot & has melted small spot in fuse panel. and truck still has a rough idle. can you help? i have already spent to much money repairing the problem , almost $800.00 dls . so i really cant spend any more. sorry, Bobby.
Jul 7, 2020 at 1:48 PM (Merged)
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JDL
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Did the trouble codes show anything? If the code pointed at a particular cylinder misfire, then you can start at that cylinder. Some of the national brand autostores used to check codes for free. Do you have the spider fuel system?
Jul 7, 2020 at 1:48 PM (Merged)
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DOEYS
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2000 chev silverado 5.3 4wheel drive no power to fuel pump only for sender checked fuse and relay all good i did notic i only have 1 source of power where the relay is do i need 2 sources and if i do where does it come from thanks
Jul 7, 2020 at 1:48 PM (Merged)
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RASMATAZ
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If its tied in with the oil sending unit it will look like this, the PCM energizes the relay coil side then the switch side will close to give power to the pump this is how it works-


https://www.2carpros.com/forum/automotive_pictures/12900_oil_sending_unit_and_fuel_pump_circuit_5.gif

Good Luck Hope this helps
Jul 7, 2020 at 1:48 PM (Merged)
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MIKE GENTRY
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My truck fuel gage hasnt' worked correctly for 75,000 miles and the truck quit the local mechanic said that it is usually the fuel pump. Changed the pump and it didn't work. Unhooked the wires and hooked straight to a power supply and the pump worked. We tried the old one and it worked. We swapped out relays and checked fuses and no issue. Not sure were to go from here. I have been told that it could be a ECM or a bad connection,.
Help
Jul 7, 2020 at 1:48 PM (Merged)
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JDL
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Welcome to the forum, Did you check for voltage at the fuel pump relay circuits? Voltage to the load side of relay is hot all the time. Check voltage for the coil side of relay, engine cranking.

you might use a noid lite, see if you have injector pulse, engine cranking? Are there any codes? Did you use a gage and check fuel pressure before replacing anything? Also, check for voltage and ground at pump connector.
Jul 7, 2020 at 1:48 PM (Merged)