fuel pump relay?

1997 CHEVROLET SILVERADO
103,330 MILES • V8 • 4WD • AUTOMATIC
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CARLOSZ71
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Noticed that fuel pump relay gets hot. Once that happens i cant restart the truck until relay cools down. Does this mean my fuel pump is ready to go out?
Oct 25, 2008 at 2:08 PM
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PEAR69
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No, a failing fuel pump will cause the fuel pressure to drop. To see if the pump is weak or failing check the fuel pressure -- it should be between 58 and 65 PSI.
A hot relay can be normal, but if there is a problem with a wire connection, this will cause a relay to heat up. A connection problem can be inside of the relay itself or elswhere in the circuit. With these trucks a corroded ground can cause all kinds of problems. The fuel pump ground often corrodes. It is located just before the fuel tank and is connected to the frame crossmember. It is a black wire and comes out of the fuel pumps wiring harness. This one little ground is the cause of many fuel pump headaches. Try removing and cleaning this connection up.

The if the fuel pump is indeed at fault make sure you replace the fuel pump chassy wiring harness connector when the pump is replaced. This connector is a "one shot deal". When these connectors are plugged in that's it -- you cannot unplug and replug in this connector. If you do the connection will arc and heat up causing all kinds of problems---this is a defect in this type of connector.

Here is the fuel pump relay location below. Check out the diagrams (Below). Please let us know what you find.
Oct 25, 2008 at 2:24 PM
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BOSTON01
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truck is not starting, already checked fuel pump and fuel relay, still won't start...could you send me a diagram of the fuel system please and direct me of what else to check to get the truck back running, thanks.
Jun 26, 2020 at 12:54 PM (Merged)
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BLACKOP555
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before i do that, are you sure its the fuel system?

have you tested ignition and fuel system?



you tried spraying starting fluid down the throttle body and cranking it? does it fire up then die? fire up and stay running?
Jun 26, 2020 at 12:54 PM (Merged)
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BOSTON01
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yes I've tried that, truck runs while feeding fuel. Seems as if the gas isn't getting to the injecter but has fuel at the fuel rail. Not showing any engine code.
Jun 26, 2020 at 12:54 PM (Merged)
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BLACKOP555
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whats the fuel pressure at the rail, dont just push on it and if fuel comes out think its good, you need to know how much pressure.

if pressure is within specs i would be checkign pulse from the fuel injectors.
Jun 26, 2020 at 12:54 PM (Merged)
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PATCHES22
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started stalling occasionally then finally would not restart. replaced fuel pump tried to start fuel pump no run, replaced relay still no fuel relaced computer (from wreckers) tried relearn and that didn't seem to be working so put old computer in and truck started for about 15-20 mins and now won't start. any help welcome extremely puzzled
Jun 26, 2020 at 12:55 PM (Merged)
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RASMATAZ
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https://www.2carpros.com/articles/car-cranks-but-wont-start

Get a helper disconnect a sparkplug wire or 2 and ground it to the engine atleast 3/16 away from ground-have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel related problem, Do you hear the fuel pump come On when you turn key on? If not check fuel pump fuse and fuel pump relay if okay-check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light. No snapping blue spark continue to troubleshoot the ignition system-power input to the coil/coil packs,coil's resistances,cap and rotor,distributor pick-up coil, ignition control module, cam and crank sensors and computer Note: If it doesn't apply disregard it and keep testing
Jun 26, 2020 at 12:55 PM (Merged)
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DOUSCHWAYNE
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My problem is somethings affects the fuel pump and only the fuel pump about every weekend for a month now. Replaced the pump, and the ground. Worked for a week, then nothing. Everything worked but fuel pump. Thought i had it figured out. Switched the relay, and fuses. Im very sure the ground is good, fuel pump works too, but only after i take things apart, play with things, and put them back together. What would make a fuel pump shut down sparatically?
Jun 26, 2020 at 12:55 PM (Merged)
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RASMATAZ
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The fuel pump comes on for about 2secs before the fuel pump relay de-activates when engine is cranking and oil pressure goes above 4psi this is time that fuel pump/oil pressure sending unit will constantly power the fuel pump.

Could be the computer control of the fuel pump relay
Jun 26, 2020 at 12:55 PM (Merged)
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ABOUTTOSMASHMYTRUCK
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I have a 1996 chevy silverado 1500. 5.7 litre auto. the instrument cluster is dead, no spark and no fuel to the rail. please help this truck is costing me a fortune
changed the fuel pump relay, worked for about 5 minutes then stopped again.
Jun 26, 2020 at 12:55 PM (Merged)
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ABOUTTOSMASHMYTRUCK
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Also, hooked up a code reader, ran through the process and it keeps coming back as a link error
Jun 26, 2020 at 12:55 PM (Merged)
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RACEFAN966
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First check fuse number 7 in the fuse box inside the truck. It should be a 25 amp. Lets start with that as that is the data link fuse. Also 2wd or 4wd? thanks
Jun 26, 2020 at 12:55 PM (Merged)
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ABOUTTOSMASHMYTRUCK
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Checked the fuse and it is indeed a 25 amp and in good condition. also the truck is a 4wd
Jun 26, 2020 at 12:55 PM (Merged)
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RACEFAN966
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Sounds like you might have a bad instrument cluster which is available from your local parts store. So do you have a digital volt ohm meter? if so we can do some testing to make sure.
Jun 26, 2020 at 12:55 PM (Merged)
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YAMAHA186
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I have replaced the fuel pump in my truck 5 times in the last 7 months and it recently went out again. I have replaced the fuel relay and fuel pressure regulator. Is there anything else that could be causing this problem. Any help is greatly appreciated. Thank you.
Jun 26, 2020 at 12:55 PM (Merged)
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DE772601
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Hello well check the connection on the top of the fuel pump there should be a 4 prong plug that they tell you to replace when replacing the pump. That plug will sometimes get hot and melt the wires causing the fuel pump to quit or malfuction. I hope this will help your problem.
Jun 26, 2020 at 12:55 PM (Merged)
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TONYDANIELS
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Question: I have 97 chevy silverado 2 wheel drive with 5.0 engine. My truck was running well until it would not start. It suddenly stopped. I used to hear a noise in the tank but when I checked the gas tank there is no noise. So i figured it may be the electric fuel pump in the tank so I changed the tank and fuel pump. but it still does not make any noise or start.

Could it be relay.

Please advise.
Jul 7, 2020 at 1:51 PM (Merged)
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MERLIN2021
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could be relay or wiring....Seems the fuse for the pump handles the PCM as well!


https://www.2carpros.com/forum/automotive_pictures/62217_LegendPU97_1.jpg


https://www.2carpros.com/forum/automotive_pictures/62217_PU97Relay_1.jpg


https://www.2carpros.com/forum/automotive_pictures/62217_Components97PU_1.jpg


https://www.2carpros.com/forum/automotive_pictures/62217_30961_mitchell_2_5.jpg

Jul 7, 2020 at 1:51 PM (Merged)