Welcome to the forum.
Why did you replace fuel pump?
Can you get a pressure gauge to test fuel pressure?
1989 EFI should be 30-40psi running, and hold above 20psi after being shut off for 30-60minutes
Revving engine in drive way isn't the same as when under load on the road
Fuel consumption is more than doubled when engine is actually pushing vehicle weight down the road.
You can mimic a bit of a load if you have it in gear foot on the brake and give it some gas.
On the fuel rail(engine) is the FPR(fuel pressure regulator), the Return Fuel Line is attached to it.
It has a spring inside that holds the valve closed if pressure is under 30psi.
You can remove the Return fuel line, there will be some fuel coming out so have a towel or ?? to catch it.
Then turn key on, DO NOT START ENGINE!!!
Fuel pump will run for 2 seconds
See if fuel comes out, it shouldn't
Thinking FPR is leaking or stuck open, bad spring, so pressure is low
Other thing is the fuel filter, was it changed as well?
Dirty filter, or screen/sock in the tank, allows some fuel to flow but as demand increases fuel pressure goes down from limited flow and engine starves for fuel