Relay help on 85 camaro 2.8
Hello there! I just joined today because I'm trying to help my 17 yr old neighbor get his first car running. It's a 1985 Comaro with a 2.8. It had the key broke off in the lock so I replaced the cylinder. He thought the fp was bad because you couldn't hear the pump prime when the key was turned to the "on" position. I ran a jumper wire from the battery and fot 40psi on my fp guage. Now, about my problem. I noticed 2 relays on the DS firewall by the brake booster. I tried to swap them out with eachother because they looked the same but still got no voltage to the pump. Then I noticed an identical relay mounted up front by the battery and mounted right to the side of the radiator on the pass side. It has 4 wires, heavy guage orange, then thin black, then thin black with a green stripe, finally a heavy brown wire. The center 12 guage black wire has 12V with the key on. No other wire gets any voltage. If I jump that wire directly to the thin black/green stripe wire, the fuel pump primes and the car runs great! Fires right up! I replaced that relay thinking it was bad, but as soon as I plug the harness back in to the new realy, the pump wont prime.
Now, what is that relay? I hear no mention of it when I search. I realize a relay needs a ground, 12V constant, 12v switched, and 12v out to the item it powers(fuel pump) Should it have 12+volts constant to the large orange wire? Does that make the large brown wire a ground? So as it sits, the colored wires are dead and the small black wires will energize the pump. It makes zero sense. Can anyone pleas help me out? I'm a Ford guy trying to help a Chevy guy so cut me a little slack.