I've been having an ongoing (2 years) battle with my fuel pump(s), I'm trying to solve my latest problem. My Chilton's book says the fuel pressure should be 40-47 psi when the car is running. I am reading 35 psi, is this low enough to make a big deal about it, or is this a sign of a bad pump starting to die?

This is a new pump, it's only 6 months old, and has less than 3k miles on it, so I am hesitant to think that the pump is bad, or is it possible I got a dud from Murrays?

There is a lot more to the story, but should I be worried about my current pump?

 

You are aware that the specification is for the fuel pressure with the vacuum compensation line disconnected? When you reconnect the vacuum line, the rail pressure (what you are measuring with your gauge) should drop proportional to intake manifold vacuum, and 36psi is a very typical number.

You also need to check the pressure at WOT/max load/max RPM... the pressure should stay within 1 to 2 psi of the "no vacuum" reading.

 

I was not aware, thanks for the advice. I'll be doing some more checking/testing this evening, when I have someone to help me watch the gauge.