No it was a crap shoot pump bought off eBay, this morning I put a Bosch pump in, since then have borrowed gauges and measured only 40lbs. Obviously not enough. So I ordered a third pump, Delphi, listed as oem, and it will be here at about 430pm.
Also found poor voltage at the pump connection, project for another time, for now I am going to run 12v directly from the battery to rectify.

 

Ok....brand new Delphi OEM pump......same thing, 40lbs.....I don't get it.....considering a 10ga shell to the block...any more ideas?

Edit, gonna try purging the fuel lines before I shoot it.

 

Oh man this sucks. Think a couple of things. You need to get the voltage at the pump problem corrected. There might be sediment clogging the filter from all the screwing around with the tank. Do you have a car you can test your fuel pressure gage on to make sure its reading right. Feel your pain!

 

Fuel filter?
The poor voltage may be at relay.. or may be bad ground.. or may be the connection at the pump pigtail. Low volt will definitely cause low pressure.

Measure voltage from the pump ground to frame.. should be no more than .1 or .2. If more than that, check grounds at the lugs atop crossmembrt over rear diff.

 

ok, picking up a new fuel filter, and I looked all over for the pump ground, are you talking about the black wire in the harness? I see no ground strap.

 

 

12v direct from battery and new ground direct from frame to the fuel pump, I removed the fuel filter and temped in a piece of rubber hose in its place. before i did all this i removed the hoses for the fuel meter body, fuel filter, and fuel pump, ran a seafoam/gas solution and 160lbs of compressed air threw each line from both directions.
When I put it all back together, I turned on the fuel pump and PRESTO!!!! I lost 10lbs of pressure, went from 40lbs to 30lbs. checked entire system for leaks and found none. WTF! at this point I could have taken it to chevy and had it fixed! I just dont understand guys.
Once again I am back to looking at the fuel pump. Going to call chevy Monday morning to verify I have the right pump and if not purchase the proper pump.
If infact I already have the correct pump application installed, what else can I possibly replace to fix this?
All of this having been said, It still refuses to hold whatever pressure it generates after the pump shuts off. Indicator bad pump? leak somewhere? if so where? To me it seems if its not holding the fuel pressure its because there is no check valve, if there is no check valve, the system is relying on the pump itself to hold the pressure. And based on this hypothesis, the pump is supposed to hold the pressure and isnt, that in itself been a dead give away that I have the wrong pump, and since a gas powered vehicle requiring 60lbs of fuel pressure is so friggin uncommon, it would be a fair assumption to say the pump is only supposed to put out 40lbs. I can attribute the 10lbs loss to a sure dead battery after a week of trying to start the engine.
Guys the section of the system from the shraeder valve to the pump is NOT at all complicated, what am I missing here?

 

Gots to be the F.Pump!

 

What about the FPR? Isnt it the device that holds the pressure in the line so the injectors have a minimum of 40psi at all times?
Maybe the one you put in is leaking?

 

I dont exactly know if the FPR is suppossed to hold pressure, I wouldnt think so, but either wayI have run the pump key on engine offwith the intake off and verified there are no leaks