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Fuel Pump: Best place?


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What do you all think is the best place to run a fuel-pump from? I want it to be triggered off of the key like it normally would. This is my sisters' car so I dont want any "you have to turn this on before and make sure you turn it off.. blah blah blah" because I dont think she'll remember.

 

Why am I asking this? For some reason or another the fuel-pump wiring stopped working. All fuses are fine, and I replaced the voltage regulator (1980 GLF coupe).

 

Thanks in advance

 

- Erik - Tacoma, WA -

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you could always run a fused power off a relay or directly off the ign relay( in the run position). just "T" into the ignition stuff in the steering column, run a power wire from there when you make sure the power is on during the RUN part of the ignition. and then run a wire (14 or 16ga.) back to the fuel pump, and find a ground point and there you go.

 

 

 

~Josh~

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Sounds similar to what I was thinking. Already have an independent ground run to the chassis and power line run out - was just hoping for a mucho-convienient place to tie into the system. Thanks for the steering column tip, easy to get to for testing / getting electrical tools in there.

 

- Erik - Tacoma, WA -

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Have you taken a good look at your Fuel Pump Control Unit?

 

That is what sends the power to the pump.

 

A quick and easy fix relative to wiring up and mounting a new fuel pump?

 

It should be the black or blue box hooked up to your hood release lever on the firewall.

 

I'd check the wires headed out of that box and see if it quit sending a signal to the pump? $3-5 at your local Junkyard.

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I've done a couple of retrofits at the regular location (near gas tank), using round universal aftermarket pumps, and large conduit straps. Worked great!! I see no advantage in sticking with the OEM setup - especially if the original mounting plate is all corroded. I like the fact that the wiring, filter, and the rust-prone sections of the fuel lines are all in the same area making a custom setup easy . If you position it just right, it's pretty much inline from the tank to fuel lines, keeping the fuel pressure steady and strong.

However, if your wiring is bad and you don't want to fool with troubleshooting it, relocating the pump against the firewall would make sense. You could configure the fuel circuit a number of ways at this location. The only downside I can think of is that the pump may not be as efficient so far away from the tank. I would probably keep a filter at the tank, and maybe add a second one in the engine bay.

good luck, John

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i mounted mine on rubber mounts right on the rear shelf under the hood. i mounted it on the pass side, and ran the fuel lines over to it and the carb, then i wired it right to the coil which worked like a charm, when the key is on, the pump is on..... and vise versa.

 

oh and i couldn`t unbolt my old one due to rusty bolts so i left it in there, just unplugged it and took off all the hoses going in and out, then i just attached the filter to the hose going up front.

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It really doesn't matter - 1981 and older subes had the fuel pump in the engine bay, and later they moved it to the rear. Both woked fine, and I beleive the reason for the change had more to do with regulations and/or noise/vibration from the pump. The pulse style pumps are loud.

 

The 1980 should have the pump in the engine bay already, and the car is not equipped with the correct vent/return line system for the under-car mounted pump. Stick with what you have. Check the FPCU as you may just need to replace this or a fuse or ground wire or something.

 

Personally I would not run any pump without the FPCU component in the wireing. It serves to shut the pump down if the vehicle is in an accident. It uses the tach pulse from the coil - if it is not present the fuel pump is not powered.

 

GD

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Personally I would not run any pump without the FPCU component in the wireing. It serves to shut the pump down if the vehicle is in an accident. It uses the tach pulse from the coil - if it is not present the fuel pump is not powered.

 

GD

 

Good point.

And remember, you can still incorporate this safety feature even if you choose to bypass the OEM wiring.

 

John

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On my 80 the power came thru the Voltage Regulator via the alternator-that was the version of the safety switch. Engine dies=no laternator output=no fuel pump power. Before I did much else i would check alternator output is 14 Volts or so with car running. Intermittent alternator caused me lots of grief in stalling for this reason, has been detailed in previous posts including wiring of a overide swtich just in case....

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Jbrand is correct, the volt reg is the saftey in this model (just replaced my volt. reg with a good used one). I'll check the Alt though

 

For those mentioning new pump and placement... I dont need a new pump, the pump in there is actually brand new (last owner replaced it) and I ran a new ground - thing runs off a switch straight from the battery just peachy. NO I am not keeping it this way - this was to trouble-shoot / get it into the garage.

 

75 Subie - When I had it run off of the + side of the coil it was only running at 6.5V therefore not really functioning. 1980's have this funky resistor pack thing on top of the coil, but thats matched to the starter circuit, not to "run".

 

Thanks for everyones input so far!

 

- Erik - Tacoma, WA -

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Well, after it was all said and done it turns out the alt was wonky and not putting out the correct voltage - after that the coil put out the right amount of power and everything was peachy.... So out of curiosity I plugged it back in to the factory connection and lo-and-behold, works just as it should. Strange thing is the voltmeter on the dash was reading right (Maybe just hadn't run itself down enough?). Oh well, problem solved with spare parts from the shed - yay for parting out dead cars!

 

- Erik - Tacoma, Wa -

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