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Discussion Starter #1
Having problems with no power to the fuel pump plug. Wife was just cruising down highway and it spit and sputtered and died. Got it towed home no fuel pump kicking into prime but if dump little gas in throttle body will fire up and die. Fuel pump was replaced not even a year ago.

So just went ahead and replaced fuel pump relay with no luck. So decided to check plug plugs back at the fuel pump and sending unit, and no power to fuel pump plug I'm not good with wiring but the plug to the fuel pump should get 12 volts with the ignition on and if my research is right there is no fuel pump fuse but a fusible link right?

Any help on how and what to test or try next would be great, before I rip the rear seat out and start tracing fuel pump wires back up front

Thanks
 

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When you turn the key to ON with the engine not running, there is only power to the fuel pump for 1 to 2 seconds. Then the ASD relay opens up and shuts down the fuel pump relay. This is to prevent fuel flowing after a crash or rollover, with ignition still on.

So if you turned it to ON, unless someone had a voltmeter *already* connected to the plug to watch for voltage, there would be no voltage showing after 2 seconds. You need to repeat the test with another person at the pump with a voltmeter already connected.

Or just listen carefully for the pump running for a second or two when you turn the key to ON.
 

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Discussion Starter #3
Bob Lincoln said:
When you turn the key to ON with the engine not running, there is only power to the fuel pump for 1 to 2 seconds. Then the ASD relay opens up and shuts down the fuel pump relay. This is to prevent fuel flowing after a crash or rollover, with ignition still on.

So if you turned it to ON, unless someone had a voltmeter *already* connected to the plug to watch for voltage, there would be no voltage showing after 2 seconds. You need to repeat the test with another person at the pump with a voltmeter already connected.

Or just listen carefully for the pump running for a second or two when you turn the key to ON.
Retried with wife turning key on still doesn't seem to be getting any volts to fuel pump
 

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I know on my car when doing the key dance checking for codes, I will only hear the pump prime two out of the three key on cycles.
 

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After a certain number of key cycles, the fuel pump no longer runs for the second or so when the key I turned on.
 

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valiant67 said:
After a certain number of key cycles, the fuel pump no longer runs for the second or so when the key I turned on.
Exactly. After that, crank it and shut off, then try again with turning the key to ON.
 

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Discussion Starter #7
Bob Lincoln said:
Exactly. After that, crank it and shut off, then try again with turning the key to ON.
That's exactly what I did I know the fuel pump only cycles a couple times when turning key on. Wiring issue somewhere?

What's the easiest way to get direct power to the fuel pump power to the fuel pump relay plug? So I can rule that out pretty sure it not the pump at least I hope not, but you never know with the quality of parts some of these auto part stores have.
 

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Unplug the fuel pump relay and insert wires into the socket to provide 12V and ground, see if that's what you get at the pump end of the harness.
 

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Discussion Starter #9
Bob Lincoln said:
Unplug the fuel pump relay and insert wires into the socket to provide 12V and ground, see if that's what you get at the pump end of the harness.
Getting 9.5V and pump kicks on with it
 

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Shouldn't be that low. Is that with a digital or analog meter?
 

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Discussion Starter #11
Bob Lincoln said:
Shouldn't be that low. Is that with a digital or analog meter?
Sorry little over 12V charger was on 2amp and don't think I had the greatest connection 1st time
 

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I would not use a charger as a 12V supply.

Nevertheless, it appears that the harness between fuel relay and fuel pump is good, and you say that the pump does activate. So there may be a fuel delivery problem:

1) Inlet sock on fuel pump may have fallen off or become clogged.
2) There may be a plugged fuel line, or a small hole/crack in one that prevents pressure buildup.
3) The injector may be clogged.
4) The fuel filter may be clogged. They are supposed to be replaced every 52,000 miles - how many since it was last done?
5) There may be bad gas in the system.
6) There may be a vent problem. Try to start/run the car with the gas cap off.
7) The fuel pressure regulator may have failed.
 

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Discussion Starter #13
Bob Lincoln said:
I would not use a charger as a 12V supply.

Nevertheless, it appears that the harness between fuel relay and fuel pump is good, and you say that the pump does activate. So there may be a fuel delivery problem:

1) Inlet sock on fuel pump may have fallen off or become clogged.
2) There may be a plugged fuel line, or a small hole/crack in one that prevents pressure buildup.
3) The injector may be clogged.
4) The fuel filter may be clogged. They are supposed to be replaced every 52,000 miles - how many since it was last done?
5) There may be bad gas in the system.
6) There may be a vent problem. Try to start/run the car with the gas cap off.
7) The fuel pressure regulator may have failed.
Thanks Bob what and how should I test first?

If I unhook the fuel lines from fuel pump and run some rubber line to gas can and turn key on should pump kick on?
 

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I would do 6) first. Then disconnect the fuel line at the filter input, point it into a suitable container, and turn the key to ON. It should pump for a second or two. It will be pulses rather than a steady stream. if the filter is not within that mileage limit, replace it.
 

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Discussion Starter #15
Bob Lincoln said:
I would do 6) first. Then disconnect the fuel line at the filter input, point it into a suitable container, and turn the key to ON. It should pump for a second or two. It will be pulses rather than a steady stream. if the filter is not within that mileage limit, replace it.
Well nothing when removing gas cap or when I remove filter input line no pump and no gas.
 

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So, it seems that the fuel pump has failed.
 

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It might run but not pump, especially, if, as I suggested, the inlet sock is clogged or has fallen off. Since you are upstream from the filter, that wouldn't be an issue.

The only other possibility would be a hole in the fuel line preventing pressure buildup, but you'd smell that.

Forgot to ask, you do have plenty of gas, right? Not relying on the gauge, but on how much you KNOW is in there?
 

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Discussion Starter #19
Bob Lincoln said:
It might run but not pump, especially, if, as I suggested, the inlet sock is clogged or has fallen off. Since you are upstream from the filter, that wouldn't be an issue.

The only other possibility would be a hole in the fuel line preventing pressure buildup, but you'd smell that.

Forgot to ask, you do have plenty of gas, right? Not relying on the gauge, but on how much you KNOW is in there?
I can't even hear it run when I turn key on I guess I'm just confused as to why get no power to fuel pump relay or fuel pump plug when turning key on, but if supply 12V directly to fuel pump relay plug pump will run. And don't you mean downstream from the filter since were between pump and filter

Like I said I'm horrible with wiring and electrical

It should have around a 1/4 tank of gas I didn't want to add more incase I had to drop tank.
 

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Jumper power to the fuel pump relay and see if the pump puts out gas. If it does, and we've already proven that the connection between relay and pump is good, then the trouble is further back.
 
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