Hi, I'm new to this forum I'm in dire need of some help with my 1989 firebird v8 305tbi. Currently the issue lies with the fuel pump not turning on when i try turning the key. Even when i turn it to accessory the fuel pump doesn't prime. When i jump power to the aldl terminal for the fuel pump it instantly starts priming and i can even start the car with that momentarily, obviously. So now im trying to diagnos the issue. First i checked the power connection to the relay, i cleaned the relay fuse and checked for 12v, it was fine. Then i went to the relay and found the wiring terminal to be in rouch shape. I bought and spliced in the new harness, hopefully correct as the colors were faded. After that i plugged in a new relay. The fuel pump still didnt prime upon turning the key. I then checked the voltage to the relay and it only read 4.88v is this supposed to be 12v can i just jump a new 12v wire to it? Also my security light turns on for like 3-4 seconds when i turn the key, i was also thinking it could be the fuel pump disable funtion? but i dont know. help please
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There is no security function on the pump

Acc position doesn't run engine functions like Ign and the pump

 

On which wire ?
Should have 12 V at the pump fuse and 12V at the org wire at relay connector all the time with key off.
Should have 12V on the green / wht wire for 2 seconds when the key 1st turned on
If you have power at the fuse but not at the relay you have a wiring problem between the two

Your car as a oil pressure switch that also operates the pump as soon as you crank the engine over , the engine should start and run on that without the relay even being installed ( just needs a little more cranking to build oil pressure up to operate the switch.
As shown below, the power to the OP switch comes from the same fuse as the the relay so your problem appears to be the supply side of the pump circuit


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