fuel pump
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fuel pump
1986 corvette
I am getting ccorrect voltage on (black) side of weatherpack which leads to power source. However, on the other side of weatherpack (orange) leading to fuel pump sending unit getting 2 volts when plugged together. Suggestions? See pictures.
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I tried that and didn't change situation. Ultimately, I am getting 0 fuel pressure at the rail. Oh, I am running two fuel pumps for Procharger. Both fuel pumps, fuel pressure regulator, fuel filter and oil pressure switch are all new.
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You should be able to easily confirm.
Last edited by WVZR-1; Aug 9, 2016 at 10:15 PM.
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Are you sure about that? Ok, let's take one step further......I spliced the two power wires directly (skipping the weatherpack) with each other....same results at 12v when seperated then together 2 volts. When I connect fuel pump #2 directly to the 12v wire fuel pump doesn’t activate. However, when I ran wire directly to battery to fuel pump #2 it comes on.
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Are you sure about that? Ok, let's take one step further......I spliced the two power wires directly (skipping the weatherpack) with each other....same results at 12v when seperated then together 2 volts. When I connect fuel pump #2 directly to the 12v wire fuel pump doesn’t activate. However, when I ran wire directly to battery to fuel pump #2 it comes on.
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Reasonably sure BUT I've no idea how you've wired the 2nd pump etc. You could have potentially created any number of issues. An early C4 sender has a filter @ the sender (internally under the flange) and if you hhad the sender removed you might notice diminished values beyond the filter (I believe).
If you unplug the Weather-Pack and that terminal is 12V and if you back probe the mating connector at that position when connected you should see the same 12V. If not you've got issues with the terminations of the terminals.
If you unplug the Weather-Pack and that terminal is 12V and if you back probe the mating connector at that position when connected you should see the same 12V. If not you've got issues with the terminations of the terminals.
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From: San Antonio Texas
If you have access to another 12v power source or a spare battery, put power and ground jumper wires directly on the pins to the tank side plug and see if your pump runs or not. That will tell you if that end of the plug and the pump itself is good or bad. Careful and don't put it across your gauge sender wires or you'll roast them!
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If you have access to another 12v power source or a spare battery, put power and ground jumper wires directly on the pins to the tank side plug and see if your pump runs or not. That will tell you if that end of the plug and the pump itself is good or bad. Careful and don't put it across your gauge sender wires or you'll roast them!
I actually tried that very thing the other day. The pump didn't work. I have since ordered a new in tank pump to replace pump #1. I am starting to think machanic wired pump #2 wrong (as direction can be reversed on that pump by flipping positive and negative wires). Therefore, when we activated pump #2 it was pushing back against #1 and damaged the pump. In this set up #1 feeds #2....
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If you have access to another 12v power source or a spare battery, put power and ground jumper wires directly on the pins to the tank side plug and see if your pump runs or not. That will tell you if that end of the plug and the pump itself is good or bad. Careful and don't put it across your gauge sender wires or you'll roast them!
The fuel sender gets 5 volts from the dash but 12 volts will definitely kill it.