Hooked up a fuel pressure Warning light yesterday, Now its on, What is the pressure supposed to be.....5psi idling now....lower when throttling....Help!!!

 

What year of truck?? I know the VP trucks 1998.5-2002 should have no lower than 8 psi. The injection pump is cooled by fuel so most guys like to see a little more. Mine is at 15psi more less all the time. It looks like its time for a new pusher pump for you

 

Just ordered one from Cummins $118.00....Dont' wanna mess around and have to buy a VP44...Wife may be mad but, not the first or last time...thanks man...

 

I think having to replace the VP will make your wife feel a whole lot worse than the cost of a lift pump.
Fill out your signature. Although a fuel pressure question is almost inevitably a 2nd gen 24 V, it helps a lot to see if you have mods, etc.

 

Also where did you hook up the sending unit ?

5psi is a little low. I have 12psi idle and 7 psi WOT with a Holley Black