What color is the fuel pump hot wire

a really really old PU
very few are running now here, uSA.
key parts super hard to find.
Service manuals (SM)
the books back then, were only made from PAPER (500pages)
no digital books then (PDF) so buy the book used off EBAY?
books not fully digitized fully or ever at all, <<< not me, I PASS.
one way to find it is to know the pumps wire colors !
and the relay with those colors is BINGO

answer fuel pump relay (im reading the schematic now)
pins reiay coil are black/ and other wht/blk.
12vdc power in is ,blk/with ( 3 fuses good to get this hot)
pump pin wire is BLUE.

so that is one way and one answer.
googling fuse boxes 37 years old is in the IFFY category.
pure luck, and your job.

I just looked at a wiring diagram of the fuel controls for this model: there is no fuel shut-off switch in the wiring. It's pretty straight forward, typical fuel pump controls: the fuel pump relay is in the under-hood power distribution center. When this relay is turned on, power is sent to the fuel pump, nothing else is in the path of the hot wire to the pump module so it (the pump) should be working.

So if pump is not on, you can diagnose the wiring right here at the fuel pump relay. First you verify the power feed for the pump is available at the relay. (One terminal at the relay will have battery voltage with key off. If you pull the relay out and use a test light, one terminal position will be hot.) Next you verify the relay is working, sending power to the fuel pump in the gas tank. You do this by having someone cycle the key to on, while you hold a finger on the relay (it's back in place) to feel it click on. You should feel it, maybe even hear it, the relay will energize every time the key is turned to on, and this is what sends power to the fuel pump.` If it all works, and the pump is not on, the pump probably needs replacing. If the pump relay is not clicking on, that's a wiring hassle, including the wire to the engine computer. The pcm is what controls the relay turning on.
Do you know if the fuel pump has ever been replaced in the car? If it is original, it has been a good long run.

Bad Ignition Switch

Worn out Fuel Pump

Worn Fuel Pump Relay Contacts

Do the proper testing

Do not replace any parts until
they fail a test

Lets start at the beginning. The engine computer grounds the pump relay. The relay gets power from the EFI relay when the key switch is on and from the starter fuse when the key switch is in the start position. Do you know if the pump relay is getting power from both sources and a ground from the computer ? Can you run a hot wire to the blue black wire going to the pump and keep it running ?

lets say you have power and fuel is pumping it goes from pump to fuel rails in one long line if fuel is at port on rail then ck injectors for hot and ground hot with key on ground with engine turning injectors get ground from ecm ,if no ground ck for bad ground wires then ck ecm ,. if no power to pump ck fuse and fuel pump relay and wire system. some times replacement parts are bad.

Your fuel pump is powered by the GREEN fuse link in the fuse link holder. If you have 2 terminals (both WHITE/BLACK wires) at the fuel pump relay that is HOT all the time (even with the key OFF) then this fuse link is OK. There are no other fuses to be concerned with.

There is also a "Fuel Pump Control Unit" located on the left rear quarter panel, behind the "B" pillar. (See Picture)

sounds like the fuel pump is not staying on or the ingtion switch doesn't make in the run position ( happens alot to vehicals take have lots of keys hang on the switch) The sparp going away is easy to check with a test light theres a connector on the distrubutor that has a heavy red wire plugged in that goes to the B+ terminal it should be hot with the key in the run position. if it's dead fix the connection at the ingtion switch ( it's on top of the steering collum and all but one wire will be hot with the key on, that one comes hot in start) if it's good the fuel pump is next it has a fuse on the passenger side firewall next to the fuel pump relay. Fuse bad or relay bad or dirty it'll act this way. The start wire entergizes the pump in crank position. then the oil pressure switch takes over and keeps the pump on. theres 3 wires on the oil pressure switch the center wire works the light the left one is fuel pump fuse power and the right one is the fuel pump. the oil switch can go bad and the connection can go bad the wire can fall off or get broken. the wire to the fuel pump may not get all the way to the pump.. You can add power to any wire on the swich with out hurting anything. all of the wires will be hot with it plugged in and running. unplugged two wires are hot with the key on ones the light ( oil Pressure light) the other is the key on power for the pump with oil pressure the switch closes and the pump comes on and it'll be powered right off the starter as it's cranking. If the switch is leaking oil its likly failed too.

Check with electric tester there should be 2 hot wires and 1 ground the lerger of the 2 wires is the one that goes to fuel pump the other is for your gas guage. make sure you check with the key on.

fuel pump relay

The engine computer turns on the fuel pump for 3 seconds when you turn the key to "ON".
If the engine does not start, the pump will not run.
When you turn the key to "Start", the fuel pump runs all the time the key is held in start.
When you turn the key on, it actiavtes the power relay, which provides power to the PCM or engine computer.
The PCM then activates the fuel pump relay, sending power to the fuel pump.
You should have one wire with 12V for 3 seconds in "run" position. This comes from the fuel pump relay to the inertia switch in the trunk and then to the fuel pump.
You should have one ground wire. black
One wire going to the fuel guage.
You may have another ground iwre ging to a diode before going to ground.