Anyone have any issues with the Fiero Store fuel pumps for the 2.8? I bought one for a tune-up (Trying to get my old turd running again) back in august. And well the pump did work, after fighting the rest of its demons, i still could not get the thing to run right. Check my fuel pressure, and well there it sits- pops up to 45psi and drops to 35 within an instant, quickly drops close to 0psi.
Tested all i could within my new injectors and FPR.
The tank is pretty easy to pull, i can usually do it myself in about 30mins start to finish, so out the tank came. Threw the old AC Delco pump that came in the tank when i got the car, assembled everything, tested my fuel pressure, jumps up to 45 and very slowly drops to 40 and stays there pretty steady.

Not bashing on the Fiero Store at all, i like their products and buy from them alot. Taught me a lesson to just spend the money on the quality parts instead of trying to save a buck and giving myself a few months worth of headaches and possible few years off my life.
Anyway, here are the results.

TFS FUEL PUMP:
https://youtube.com/shorts/...?si=T4pzl1mLM2WfRySi

AC DELCO FUEL PUMP:
https://youtube.com/shorts/...?si=-RQ25ytdm4Qq_-NR

If the fuel pressure drops to zero then it could be an electrical connection break, the pump or the regulator. I would first suggest measuring the voltage at the relay connection to the pump to see if that remains constant.

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"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
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You might have a leak at the hose connecting the fuel pump to the discharge line.

If the car hasn't ran in a long time,
You could have pushed debris into the fuel pressure regulator causing it to partially stick open.
An injector might have stuck in the open or partially open position as well.

[This message has been edited by fieroguru (edited 11-14-2025).]

quote Originally posted by fieroguru: You might have a leak at the hose connecting the fuel pump to the discharge line. If the car hasn't ran in a long time, You could have pushed debris into the fuel pressure regulator causing it to partially stick open. An injector might have stuck in the open or partially open position as well.

The car had only sat about 2 years before i got it. Break in the line wasnt the issue. It was just the pump from the fiero store

Your Fiero Store fuel pump is probably the same one available locally at Autozone, O'Reilly's etc. Same part used in numerous GM vehicles.

I've always paid more to get the AC Delco part and they've always treated me well.