I have a 2003 chevy suburban Z71.
It won't start very good, and when it dose it stumbles till it catches it self and then it runs fine. To get it to start I have to turn the ignition on several times to prime the fuel rail then it will start as I said earlier.
I put a fuel pressure gauge on it and when I turn the ignition on to prime it, the gauge barely shows any pressure, but when I finally get it started it only shows 40 psi at the fuel rail and the gauge needle pulses 1 or 2 psi.
It done this a few time about a year or two ago then went away, but now it dose it every time I try to start it warm or cold.
Thanks.

 

There is a vaccum line on the fuel press. regulator. Turn on the key and then pull the vaccum line off and if theres fuel coming out of the reg. then the diaphram is shot. If not then look at your pump.

 

Sounds like a clogged fuel filter.

 

I'm kind of having the same issues. It tajes a few try's to start and when it does the rpms sr

 

Drop way down as if it's going to die out. The fuel pressure is normal and the fuel filter was just changed out and no difference.??