Yea see I just installed a 383 stroker in my 87 Iroc. I have the mallory 4309 and all and Iam trying to figure out how to get my fuel pump to squirt fuel out of the lines and turn on. Before it was a 305 tpi. All the wiring is still in the car. I need to know how I can get the pump running. I am getting power to the relay, but when i hotwire the relay up to the battery I get just a click, but the pump doesnt start running. What wires do I need to connect up? to get the pump to run? any help would be greatly appreciated. thanks in advance. By the way The new motor is going to be Carbed, So anyone whos done this swap before please help, thanks.


Iroczman380

 

Im not exactly sure on the wires but if you do a search you will find your answer, it has been covered before.

Good luck

 

I ran a 12 volt hot wire to one of the wires in my fuel pump relay. I had to do that to get it to stay running with the key.

 

If you kept all the wiring, pour fuel into the vent tubes on the carb to fill up the bowls. Now start the car. The second you get oil pressure your fuel pump will turn on ...IF you kept all the wiring.

From the factory when you turn on the key the computer will turn the fuel pump on for a few seconds to prime the system. After that its controlled by oil pressure and has nothing to do with the computer.

Worse comes to worse you can completely rewire it, which isnt very hard...

 

Here is what you do, i did this 3 days ago on my new motor.

Fold down your backj seats, pull up the carpet in the middle, you will see 3 wires, black orange and tan, on my 87 IROC, the tan wire on mine was the one for power to the pump, tap a wire into the tan wire and run it towards teh fuze box, and connect it to the red wire in the corner of the fuze box marked IGN then put a switch inline on the wire you ran from the fuel pump tp the fuze box and now you have a fuel cut off swich

The car will die after about 10 seconds when you flip the switch to off, its a good security measure....

 

Hooking your fuel pump up directly to the ignition is borderline silly. It *NEEDS* a relay to operate properly or it'll eventually fail. I gauruntee the toggle switch you have your pump hooked up to will die on you within a few months. Why? because it can't handle the massive amount of current the pump draws through it. Plus, lets say you get into some massive car crash and are unable to turn that switch off, or turn off the ignition? You have 30+psi of fuel pumping out of your tank. If I had to chose a way of dying it wouldnt be burning to death ...Thats why you should have a oil pressure switch. Engine isnt running, no oil pressure, no fuel pump.

 

Hey guys,

Well i found the tan wire and i gave it 12v, and fuel started squirting out. I was quite happy. Now the question is how should i wire this up. Should i just run a switch to my dash, so Ill flip the switch on then start my car, or Should i run it into the ignition?, I dont think that would be to bad would it? Then when you turn the key on itll start pumping. I no you all are crazy about having the oil pressure switch, but I frankly dont see how its going to work without the computer, Because before the relay was powered through the computer, and not a 12 v hot source. SO even if it goes through the relay, and all the wires are there, with 12 v goin to that tan wire its not gonna matter if theres oil pressure or not cause its gonna start pumping. But anyway if you guys could give me some suggestions that would be great. Thanks alot , im just trying to get this 383 running to the best of its ability, so feel free to correct me if im wrong, thanks


IROCZMAN380

 

I see the search button is still missing!


DO NOT wire it to a switch


DO NOT wire it to the ignition


You ask for advice people give good advice to you SO TAKE IT!!!!

 

As I already explained the oil pressure switch is NOT controlled by the computer in any way. The only time the computer controls the fuel pump is when you first turn the key on. It primes the pump for a few seconds to get the lines full of fuel then shuts it off. Now when you begin turning the motor over oil pressure builds which flicks a switch and poweres the fuel pump relay.

Rewiring it isnt a bad idea at all but rewire it in the same fashion its already wired. This way you can remove the useless engine harness and free up tons of space under your hood. Off the top of my head I don't know the wiring but any basic repair manual should tell you exactly what you need to know. Its a great idea to keep the oil pressure switch but of course you dont NEED it. However, you MUST use a relay or you'll eventually damage stuff.

 

wanna hear something weird? My oil pressure switch isnt hooked up and my car runs fine. Seriously, the wires that go to the ops and the one for the dash light are just hanging.

 

hows the fuel pressure from the pump? dont forget that carbs like around 7 psi.

 

right now i still have the 2.8 in it.

 

Well, if it fails it fails, **** it, i die i die, oh well..at least it runs, ....

 

You will be stuck someplace when it does fail. And why take the time to put in a 383 and be a cheap *** on a $10 relay?

Your ghetto switch will not last long at all, it can not handle the current.

To each his own, good luck with the ******* rig.

 

Here's anbother take - I wired in a toggle switch into the oil pressure switch wires (oil pressure switch is still connected, just spliced off 2 wires and put a switch on it) Now, even when the car isn't running, I can flip the switch and get the fuel pump to come on and prime the system. Then I shut it off, with the bowls full, and after the motor starts the pressure switch takes over.

working fine so far - I don't even have the ECM in place any more (sold it with the TPI system)

 

I've been running an AFPR with a 'ghetto' wired factory fuel pump without a single problem for OVER a year now. If you noticed that the factory wiring for the FP Positive (brown wire comming from firewall) is not all that heavy...meaning that not too much current runs through it. I wired that to an oil pressure switch. When I turn over the engine the pump will kick on. When I turn it off there is still fuel in the bowls for my next start. Never been any problems; infact this little setup SAVED my 350 when the oil-pump input shaft broke! The oil pressure died and within 30 seconds my car shut down. When I tore her down the bearings were still good!

Anyway, wire it to an oil pressure switch and you'll be ok.

my working .02