how is it that my stock lift pump and my aftermarket lift pump are not working but my truck is still able to run?????? I just dont get it!!!!!!!!!!!!!!!!!!!!

 

nobody HUH?

 

The injection pump will pull it's own fuel for a while. Just for a while though, til it burns itself out. Better get the lift pump replaced soon or you're probably going to be buying a new injection pump as well.

 

I see you have the Glacier lift pump, is that the Fuel Boss??

 

When the lift pump fails and the IP has to suck it's own fuel there is little to no return line fuel to cool and lube the pump even though the engine runs fine.
IP failure is on it's way...

 

It's my understanding that the CP3 CAN NOT pull its own fuel. Only the VP44 could do that trick..Briefly..

 

My CP3 never has pulled fuel.

 

CP3 is NOT an injection pump, it's a two stage high psi pump. Injection event on a common rail is at the electronic injector. That said the CP3 is capable of pulling fuel, however under load it usually starves and is not capable of reaching the setpoint threshold......and I've seen more lift pumps failed on common rail trucks that I care to think about and have yet to see one "kill" the Cp3.

 

I've gone through 2 LP,s. That has been exactly the case with mine. First one would idle ok, but die as soon as you put a load to it. 2nd just died. CP3 is fine.