09 Tahoe, New fuel pump.. fuel rails dry

[Brandon2489]

Well...What did you figure out?

 

[Russ]

Even an older Snap-On scanner has bidirectional controls that can turn the fuel pump on and off. No one should be tied to a dealer when there are a million independent shops that have good equipment and educated mechanics.
The first thing anyone should do before replacing a fuel pump is verify that the power and ground to the pump motor is good. Without power and a good ground, you have nothing.

 

[CBIII]

nah I still don’t think it’s the fscm. So the purpose of the fscm, is to A fire the pump to prime in KOEO, and B to fire it when the engine is cranking. So since that happens voltage is being delivered when it’s required, correctly. What I am thinking now is that there is a split in the plastic line in the fuel pump assembly that’s squeezed open when the top portion is compressed down In the tank. I mean it worked when I tested it in the five gallon bucket. I will be dropping the tank again tomorrow and removing the pump to check this.

As someone else who came here to chase fuel pressure/pump woes, I'm in a similar boat. Following though.