I need to rewire the power to my in-tank fuel pump. The wire is faulty between plug in engine bay down to pump. Jumped the pump to make sure it was good. Need some suggestions on running a new power wire and would like to keep it as stock as possible. Please help....
ya, that could work. have you tried unplugging the fuel pump relay and applying power from there back to the pump..
You can splice it, yes, if you know where the hiccup is in the line. Or (more involved) just replace the line. My intank fuel pump doesn't work as well and I noticed the previous owner just bought a universal one and installed it under the hood instead of removing the bed. I plan to go original though... one day.
Havent checked power from relay back to pump but tested power at harness plug from ignition and it has power. I have my oil pressure sending unplugged and have key in on position. Whats a bummer is i just finished installing my weber and my pump worked fine before
i think the fuel pump doesnt run with out the oil sender plugged in. Or i could be getting my cars confused, its been a long week with very little sleep. the point of testing from the fuel pump relay back is you can verify the wire is good, if you got power to the relay, and apply power after the relay and the pump works, then the relay $hit the bed...easier fix then running a new wire.
Fuel pump is wired through the oil sending unit so if the pressure is not up high enough the fuel pump wont work. Safety thing I guess and my oil light is on. I havent ran the truck for a couple months. I had the same problem before when the pump was bad. I will check power from relay plug down to pump next...
Just a thought ,while ( if ) the pump is removed,replace it with a Vemon pump . More out put than the stock unit & less money! Plus will be new & good for many years!
I just replaced the fuel pump on my 78 a few weeks ago. I had a hell of a time getting the new pump to work...not enough power getting to the pump. The problem ended up being an insufficient ground at the pump. One of the mounting screws for the intake pump has a small black box attached to it that's the ground. I ended up running a wire from that to one of the mounting bolts for the tank and that fixed the problem. Starts up everytime now. While I had the tank out I took it in to have it cleaned...that thing was filthy. Hope that helps
ok........... first off was checking wrong power wire. Checked all wires for continuity and all check out good. Worked my way back to relay and found that have no power thru relay back to harness plug in engine bay. Switched with another relay and still nothing. With ignition on, have power to 2 wires on relay plug. How do I check the relays? I will next hook everything back up and check power from relay plug to fuel pump. Any other ideas?
Well, they just said that having your oil pressure sending unit unhooked = booboo fuel pump, I guess that makes a lot of sense, because for one if the engine has no oil pressure, I guess the easiest source for it to kill the engine the quickest would be to have, some way in series with the fuel pump, so if the light goes on, the fuel pump goes off... Get it? But good luck with diagnosing your situation!
Can jump fuel pump from relay plug. But have no power to pump thru relay. Dont think they sell new relays....
With my key on i check power at relay plug and have 2 solid powers on oil sending side and a faint power on the middle. Do i have a bad ground somewhere? I removed evap canister and smog pump thing mounted on inner fender. I took the resister off that and plugged it back in. Also regrounded the fuel pump to a better location. What should i check next?
Hope this helps... This is how a relay works in general. Notice that they are labeled with numbers. I'll use the numbers as reference: pin 85 is normally your accessory power (power from ignition for example) pin 86 is normally your ground pin 30 is normally your main power (in your case, 12V battery) pin 87a is a "normally closed" path to the 12 volts coming from pin 30 pin 87 is a "normally open" path to the 12 volts coming from pin 30 OK, so looking at the picture I attached, the internal coil which is on pins 85 and 86 is actually an electro magnet. When power is applied to pin 85 (grounded on pin 86), it physically switches the arm (87a --- 30 path ) over to (87---30 path). This means, if you have power applied to pin 30 ONLY, you will instantly see power on pin 87a. When applying power to pin 30 AND you apply power to pin 85 (86 grounded of course), the internal "coil" or "magnet" will switch the path and see the voltage now on pin 87. Now that I've confused you, Here's a tip: When testing your relay with power to pin 85 and 86 to ground, you can actually hear an audible click coming from it. This is the sound of the switch engaging over to pin 87. Finally, with all the relays I have dealt with, I have never had a relay go bad on me. It's usually a grounding issue to it (pin 86). Good luck
What grounds should i check? My fuel pump worked up until i did a head gasket and removed evap canister and smog pump thingy(vacuum lines ran into it) on inner fender. Im sure swapping the carb did nothing...
