EFI Fuel Pump not turning on.

[460.465USMC]

Hi Todd. I just went through this issue as well [no 12V output from the PCM to the fuel pump] with my Gen 3 first start. My PCM is of the Oct. 2020 vintage, so not sure if yours will behave the same as mine.

As part of my First Start prep. I manually ran the fuel pump to fill the fuel lines, checked key electrical connections, etc. I expected the fuel pump to run for a short burst (1-2 seconds) with the key (or Digital Guard Dawg in my case) in the Run position, but it did not. However, the motor cranked over the first attempt without issue. After the motor cranked over for the first time, I could hear the fuel pump burst. And, it does so now every time the key (or push button) is moved to the Run position. So, don't be surprised if your PCM doesn't output the 12V to your RF fuel pump relay before first crank.

The challenge with my first start was getting the fuel system purged. It took many, many iterations of this: crank the motor over, motor sputters for 1-4 seconds; motor dies.

If you're interested you can hear/see this in the videos I posted. Just passing this along in case it's helpful in your situation.

[facultyofmusic]

TL;DR: No issue with first start. ECU started acting like the instructions said it should after first start. Exactly what Chris described in post #41.

Got my engine started yesterday. After I turned it off and tried starting it again it behaved the exact way Ford instructions said it should behave. Now when I turn on the ignition switch I hear the fuel pump pumping for about a second before shutting off. Everything is now consistent with the instructions.

What I'm seeing is consistent with what Mike Everson saw, where the ECU kinda just "fixed itself". My guess is that when turning on ignition switch I didn't have some stuff plugged properly so the ECU was in a mode that only pumps fuel when it detects crank motion. Now that everything is working as expected, the ECU has reverted back to its default behaviour. Sounds like it's just a Gen 3 ECU quirk. I'd be interested in what Ford techs say about this. Regardless, I'm glad things turned out fine.