so anyway months back i had an issue keeping my car running. basically its an 89 rs that came with a 305tbi that i converted to a carbed 350.

car ran fine until last summer, kept losing fuel pressure

anyway, i just finished putting a new fuel pump in it which i could hear prime when i turned the key. the car still didnt seem to want to run after a few minutes so i started experimenting with the fuel pump relay. i inplugged the relay on the fire wall by the brake booster, and started jumping the connections with a small piece of metal, and could get my fan to run (my fan is wired right to my key on) but no pump. anyway after that i couldnt get it to do anything anymore and plugged it back in, and now the pump wont even prime.

maybe the wiring is just shot? i dont know but im absolutely sick of my car not running, and this stupid 80s safety crap and i was actually experimenting on ways to just rig a switch for my fuel pump so i can just make the damn thing run when i want it to.

anything anybody can tell me is helpful, i dont know anything about wiring.

 

Sounds like you were messing with the fan relay that is right next to the pump relay and looks identical except the fan relay has four wires going to it and the fuel pump relay has five

 

this is what i was jumping

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okay that definately is the fuel pump because if i put power to the 'pin' on the far right of the picture i can get fuel. for some reason the hot lead on that connector isnt working

 

There is a fuse mounted on the fender near the charcoal can , it don't look like a fuse but it is , and that's the fuse you blew when you were jumping the wires . Always remember , a relay will usually have a + and a - for the coil , as well as a + and a fourth connection leading to the device the relay is controlling . When you were jumping connections you likely touched the + to the - and that's why the fender mounted fuse blew .

 

ah ok. ill take a look for that fuse when i get home.

im just going to ask here since this is all part of an ongoing problem

i outlined it here https://www.thirdgen.org/forums/carburetors/740527-please-help-dying-hard.html

my car simply won't run. i cant get proper fuel pressure consistently. assuming ive replaced all the tank components (sender, pump, filter) what would be the culprit? fuel relay? oil sender? ecu not getting signal from distributor?

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okay i replaced that fuse but now im sort of back to step one

ran the car for about a minute and then fuel prssure dropped off once again (i have an external gauge)

any ideas?

 

Fuse blow again?

 

no, fuel pump primes now but doesnt seem to stay on

 

Will the car start with starting fluid?

 

When the fuel pressure seems normal and the vehicle is running, and you shut it off, does the pressure shoot to 0, or does it hold?

Put a test light on the wiring to figure if the main relay power is lost when the FP drops off. And then on the relay switching circuit to see if switch-on power is lost when the FP is lost.

You could have a leak down of pressure, or the power is being lost. Narrow it down instead of bitching about 80s crap that is more reliable and easier to troubleshoot than the 60s crap your old relatives lied to you about.

If it starts with fuel pressure, this is a redundant test.

 

jmd, he says

Not sure just how deep the "won't run" thing goes... hence the starting fluid question. He doesn't seem to be very systematic about troubleshooting. Can't tell if it's a single defect, multiple defects, etc.

 

If it's a older 350 you may just want to switch to a mechanical pump on the block. I'd hate for you to end up putting a toggle switch on it. Are you running a return style regulator, if not maybe you could be overworking the pump after a few minutes of running.

 

How is your fuel line set up? How is the return line ran, since you are using an electronic fuel pump, where is your fuel pressure regulator, some pics if you can.