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Old Sep 14, 2018 | 10:15 PM
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Default fuelpump

1985 corvette has juice at new fuelpump relay but not at fuelpump. where do I look next?
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Old Sep 15, 2018 | 07:31 PM
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Originally Posted by xkahn
1985 corvette has juice at new fuelpump relay but not at fuelpump. where do I look next?
Why are you expecting it at the fuel pump? It gets 2 seconds of charge and that is it. After that, it needs the ECM to detect ignition pulses. How did you determine there is no power at the pump but power at the relay? Shouldn't there be power to the relay and when the signal is given from the ECM, the pump "turned on"?
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Old Sep 15, 2018 | 08:46 PM
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What kind of pump did you put in the car? Might be wired backwards. Aka, negative and positive switched. That would make the pump blow and not suck.
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Old Sep 15, 2018 | 08:50 PM
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Originally Posted by 1993C4LT1
What kind of pump did you put in the car? Might be wired backwards. Aka, negative and positive switched. That would make the pump blow and not suck.
People can change sex and still blow or suck.

I guess we need to know the process he used to determine no juice. As my math instructors used to say "No working, no credit". If he probed the wires when he turned the key to run, it might show a momentary blip and then nothing but what do you expect? The pump is only hot when the motor is running FOR A REASON.
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Old Sep 15, 2018 | 08:59 PM
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The ECM applies a ground signal to relay to energize fuel pump to " prime" fuel system
there is oil pressure switch that will apply 12v to fuel pump once oil pressure is over 5 psi.
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Old Sep 16, 2018 | 12:54 AM
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Have you checked the fuse? The fuse is in the circuit between the relay and the fuel pump.

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Old Sep 16, 2018 | 12:56 AM
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Originally Posted by Hot Rod Roy
Have you checked the fuse? The fuse is in the circuit between the relay and the fuel pump.

But if the relay gets power going to it BUT no signal to send that power to the pump, it could be a problem
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Old Sep 16, 2018 | 02:04 AM
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Default Fuel pump

thx for the reply I wrongly assumed the fuel
pump received current all the time. This started as a intermittent problem and finally will not run at all. I am going to replace the fuel pump and see what happens. With the key on there is no current at the fuse according to my test light. Any advice is greatly appreciated
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Old Sep 16, 2018 | 02:28 AM
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Originally Posted by xkahn
I wrongly assumed the fuel pump received current all the time. I am going to replace the fuel pump and see what happens. With the key on there is no current at the fuse according to my test light. Any advice is greatly appreciated.
You're asking for advice:
1. Get a copy of the FSM (Factory Service/Shop Manual) for your car.
2. Don't throw money at a problem when you don't know what the problem is! If there's no power at the fuse, the fuel pump CAN'T run!

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Old Sep 16, 2018 | 07:50 AM
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Originally Posted by xkahn
thx for the reply I wrongly assumed the fuel
pump received current all the time. This started as a intermittent problem and finally will not run at all. I am going to replace the fuel pump and see what happens. With the key on there is no current at the fuse according to my test light. Any advice is greatly appreciated
IT will only show up for a second or so. You'd have to have the DVOM on all day long, turn the key and quickly notice it. IF anything, I'd replace the relay if you want something to replace.
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Old Sep 16, 2018 | 09:09 AM
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Originally Posted by xkahn
1985 corvette has juice at new fuelpump relay but not at fuelpump. where do I look next?
apply 12v to terminal G on your aldl....just went through all of this on my 85......if no results, get a separate battery, apply 12 v and ground to the grey and black (ground) on the pigtail going into the bulkhead on the tank....if no fuel pressure, start looking down that line to the fuel pump.....I found bad ground, and poor connections at the bulkhead.....also, if you didn't bypass that little connector above the fuel pump line....name escapes me at the moment, the fuel line could be blowing out when the pump pressurizes, and blows gas back into the tank.....good luck.... I 'm assuming you have a pressure gauge on you schlader valve
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Old Sep 16, 2018 | 09:27 AM
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Think you are talking about the pulsator??^
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Old Sep 17, 2018 | 07:02 AM
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Originally Posted by 1993C4LT1
Think you are talking about the pulsator??^
thanks, that's the term....didn't replace it the first time I went in there....found the fuel line blowing out every time I energized the fuel pump.....replaced it with a longer hose, have had no problems with that part of it since....getting old's hell
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Old Sep 17, 2018 | 07:32 AM
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Originally Posted by playsdixie
thanks, that's the term....didn't replace it the first time I went in there....found the fuel line blowing out every time I energized the fuel pump.....replaced it with a longer hose, have had no problems with that part of it since....getting old's hell
Where did you get the fuel line to replace it with? All can transmit fuel inside but some can be submerged and others cannot.
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Old Sep 17, 2018 | 07:51 AM
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Originally Posted by aklim
Where did you get the fuel line to replace it with? All can transmit fuel inside but some can be submerged and others cannot.
racetronix..
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Old Sep 17, 2018 | 07:55 AM
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Originally Posted by playsdixie
racetronix..
And the first time they also sent you a hose too short which caused the blow out?
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Old Sep 17, 2018 | 04:30 PM
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Originally Posted by aklim
And the first time they also sent you a hose too short which caused the blow out?
NO originally just bought a pump , kept the pulsator and old wiring....sent for a new kit when I discovered the problem....
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Old Sep 20, 2018 | 07:07 PM
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Originally Posted by playsdixie
apply 12v to terminal G on your aldl....just went through all of this on my 85......if no results, get a separate battery, apply 12 v and ground to the grey and black (ground) on the pigtail going into the bulkhead on the tank....if no fuel pressure, start looking down that line to the fuel pump.....I found bad ground, and poor connections at the bulkhead.....also, if you didn't bypass that little connector above the fuel pump line....name escapes me at the moment, the fuel line could be blowing out when the pump pressurizes, and blows gas back into the tank.....good luck.... I 'm assuming you have a pressure gauge on you schlader valve
my problem is intermittent. it just started working again just before I was going to try and hunt down the problem. where exactly did you find a bad ground/ at the firewall. what connections were bad? thx. by

when you say bulkhead do you mean firewall in engine compartment? anything lose under the dash?
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Old Sep 21, 2018 | 11:45 AM
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There is a bulkhead on the top of the fuel sending unit. Top, right side.
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Old Sep 21, 2018 | 11:56 AM
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Bulkhead connector
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