So I have searched and searched and im sure I overlooked the answer. so please let me know if I did.

I'm having intermittent starting. When it starts it starts the rest of the day no problem. Normally it wont start in the morning.

I hooked up a fuel pressure gauge

just turning the key on i got 50. (which I know is to low).

running goes up to 55-58psi 60 if i rev it up a lil

now when its randomly acting normal.

turn the key on it goes to 60. (starts right up)

So im looking for some reassurance. does my fuel pump need changed? or could it be something different? should I get the adapters to check the pressure at the filter? any advise would help

The pump was replaced a year ago trying to diagnose this problem then parked. Along with fuel regulator, crank pos sensor. I don't know the brands. (Someone else did it before I got it)

thanks in advance.

 

Update to things I've tested.

The pump comes on when I turn the key on and off.

Today the highest pressure was 48 ish.

Tomorrow I'm going to check fuel pressure at the filter.

Maybe the guy who changed the last pump got a bad one? He said it was an air tech or something. From what I've read ac delco or Delphi is the way to go. Is one better the. The other?

 

You definitely have a fuel pressure problem. It could be the fuel pump, but it could also be the fuel pressure regulator. The best way to test this is to build an adapter to test fuel pressure right at the fuel filter, thus eliminating everything but the pump. If your fuel pressure is still low testing at the fuel filter then you know to go ahead and put a new AC Delco pump in it. Do NOT go with a cheap aftermarket brand fuel pump. S-series trucks eat the cheap pumps super fast.

Captain Hook has posted on here several times the instructions for making the adapter. It shouldn't cost more than a few dollars to do it, and isolating the problem is a better idea than just going ahead and throwing parts at the truck.

 

Just got done testing fuel pressure at the filter.
Initially I got 50

After playing with it a lil (jumping the pump with a wire about 2 dozen times)

Got it to about 55 ish.

 

5 minutes the pressure has dropped from 55 down to 45.... Guess I'm putting in a new fuel pump.

 

Yep. Glad you could narrow it down, and I hope that dropping the tank goes ok for you. Sometimes they can be brutal if the strap bolt is seized.

 

well that's the weird thing. I know the person I bought this off of changed the fuel pump. maybe the off brand he bought was bad out of the box? Is there anything else I should change or check while I am this deep in dropping the tank? Someone told me something about the connectors for the pump or something...

 

What pressure numbers should I see with a new pump???

 

fuel Pressure Vin code "X" should be 58-64 idling P/N and drop 3-5 psi in gear. should also raise 5-10 psi under hard acceleration.
fuel Pressure Vin code "W" should be 60-66 idling P/N and drop 3-5 psi in gear. should also raise 5-10 psi under hard acceleration.
also do a voltage drop test on both the + & - sides at the pump. Change the connector to the 4- flat one. GM upgrade the poor quality 4-square one. Airtex fuel pumps have improved their quality in the last few years greatly. the sending unit is the down fall. but Airtex now gives them a lifetime warranty and the new connecter is included in most pumps. I got both my Venture van and my S10's at advance a/p. Venture van is 3+ years and s10 is 6-month with no trouble.