I need to relpace a fuel pump on my Saturn L100, where is it ?

Ignition module , anti-theft system killing it , fuel pump , fuel pressure regulator , are a few thing's that can cause this problem . Suggest you take it to a qualified repair shop that has the tools and the knowledge to diagnose this condition .

1. Fuel pressure reads 60 psi.

Is the security light flashing win you are tuning it over

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You have a fuse / relay box under your hood. My 2002 L100 special edition, 4 cylinder, is located near the battery. You have a relay and a fuse in series. A fuel pump operations check, section 4-3 of the Haynes Saturn L-series 2000 to 2004 manual, you can hear a soft whirring sound for 1 to 2 seconds when you turn the ignition to the ON position. I can confirm mine makes this sound when I do this. Good luck with the fix.

Note, I had a crack in my fuel pump, but I took it to an ex-Saturn dealer 4 or 5 years ago because I did not want to mess with it at the time. They had the part and fixed it in 4 hours, but it also cost me $1000 to replace the fuel pump and install a new fuel filter.

Here's a link to the P0300 code and possible causes.Sounds like clogged fuel injectors. https://www.autocodes.com/p0300_saturn.html

Well the relay gets power from the pump fuse located in the fuse box under the hood. It looks like the fuse gets power from the battery.
Are any other circuits dead with the key on ? Do you see any fuseable links around the battery that might have failed ?

For the original question, we had the same issue with a Saturn L100 - the fix was installing a new BCM - (Body Control Module).

yes you do,make sure all the lines and electrical connections are disconnected before you drop the tank all the way.change the fuel filter at the same time.

THERE IS USALLY AN INSPECTION COVER ABOVE THE TANK WRE YOU CAN THEN REMOVE THE SENDER UNIT AND REPLACE PUMP

Sound like a fuel problem check and make sure that fuel pump is working efficiently or at the time when Engine dies check for whats missing its either gas or spark . Get back to me if you need more help. ps on those cars if its loosing spark there is an igniter that's mostly to be blamed. Good Luck