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Discussion Starter · #1 ·
What should the voltage be back by the tank? I have hot wire kit and walbro 340 pump. Behind the alternator was 12.4 and by the tank was 9.5 volts.
 

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was the car running when you tested it
 

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It should be within 2 tenths, or better of the voltage at the alternator.
 

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12.4 would be normal battery voltage..if car was running it would be higher...or have I had too many beers
 

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i would hope that 12.4 is not running , running mine is 14.5 at the alt and damn near that at the pump
shouldnt be much of a drop , its a 10awg wire direct from alternator
 

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hi pauly...that why I was asking if car was running when he checked the voltage...if it was not he would see that voltage drop
 

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kinda hard to have the pump running if the engine is not running...unless you jumper the connector to force it to run...and then, there is not much load on the pump so the drop should not be very much.

Assuming you were checking the correct wire, try putting the meter between that wire and the car body and read the voltage drop...just in case the grounding is the problem.
 

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if he had ignition on but not running the pump would run (prime) and then I am sure you would see a voltage drop...please correct me if I am wrong :D
 

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pump will only prime for 3-6 seconds

to test plug the underhood lamp wire into the fuel prime connector behind the alternator and the pump will run constant
 

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thats what I like about this site...learn something all the time...pauly you go to e-town to-nite
 

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should have tried but weather was cloud after cloud of rain like every half hour it rained through the day , mostly it was clear but its damp now.
 

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Pump is normally triggered for about two seconds when the key is turned on -on Regals anyway.

I was never fast enuf to get to the back and see what it read. :D

Jumpering the Test connector will keep it running...should be about the same drop that way as when running...just lower voltage overall. :)
 

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Car running or not, FP running or not, ign on or not = moot! Proper voltage should be within .1-.3 V--NOT 2.9 drop indicated,,, Either there is a connection problem--or, like has already been said, perhaps 9.5V measurement probed on wrong wire???
 

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Discussion Starter · #16 ·
Tested with key on and car off. I checked the wrong wire. Will recheck correct wire. Thank you.
 
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