I won't replace a working fuel pump without verifying the power supply and ground. It's more than just a "pump", there's an electric motor in there, too.
ABSOLUTE MINIMUM:
1. Verify supply voltage with the pump RUNNING, as close to the pump as practical--which is generally the three-wire connector in the harness just before the harness goes up and over the tank. If the alternator is putting out 14+ volts, the pump better be getting 12 volts. More is better.
2. Verify voltage on the ground wire with the pump RUNNING, as close to the pump as practical. Less is better, anything over 1 volt is a problem.
3. Airtex says most repeat failures are due to debris in the tank that wasn't properly cleaned-out. I don't know how accurate that is, but that's their story.
4. Install a new filter sock on the bottom of the pump, and assure that the main fuel filter isn't restricted. With the pump removed, assure that none of the supply or return plumbing is restricted--no pinched hoses, or crushed metal tubes.
5. Install a new in-tank wire harness if the original has ANY sign of distress, such as corroded terminals on the wires, or swollen insulation. See photo.
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Replacement harnesses are generally longer, to fit as many vehicles as possible.
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6. Verify fuel pressure and volume after the pump is installed. High fuel pressure can be a regulator problem...or restricted return plumbing.
Optional, but strongly recommended if you have the tools to do it:
7. Verify amperage draw of the fuel pump, with the pump RUNNING. Typically about 6 amps, can vary depending on application. Amperage can be tested anywhere in the supply wire to the pump, or even at the ground wire for the pump, but you're already at that rearmost connector to check voltage.
8. Use a graphing multimeter or a digital oscilloscope, and a low-amperage probe to GRAPH the amperage draw of EACH INDIVIDUAL MOTOR ARMATURE BAR. The resulting graph is like a fingerprint--they all look the same to the janitor, they all look different to the detective. Each armature bar will have it's characteristic pattern on the graph, but they should all be reasonably similar. Once you figure out how many armature bars there are, you can also calculate the RPM of the electric motor.