Is the 11 and 14 from each bank, or what? If they are, then they are getting close to the high end. IIRC GM specs no more than 15ML returned per bank after 15 seconds of cranking at 40MPA for rail pressure. And as said above, the -450MM3 of fuel is a scan tool issue. You should be seeing 7-9MM3 of fuel at a hot idle for an 01 with stock tuning(the 600 RPM idle lowers it down a tad from later trucks).
The pump will help, but excess return rates wil lalso cause low rail pressure and limp mode.
I don't think the 2ml is going to be the low rail pressure cause. I have done a couple lb7 with 20ml return that had no issues but smoke and rough idle.
You said you had 11 and 14, so thats 25. GM specs max return rate to be 30 for the injectors. I know I had one before that was returning 8 on one side and 30 on the other and it couldn't build past 14K PSI at idle. you also need to check the CP3's return from the bypass port. Shoudl be no more than 20ML, but ideally less than 8 IIRC.
