97 Blazer Cold Start Problems

I have a 1997 S-10 Blazer with a 4.3L (W), lately have have been having problems starting it when it is cold.

I performed some diagnostics last evening and here is what I came up with. Looking in the Chilton's manual for the 97 S-10 Blazer under Fuel Testing page 5-10, item 7. "Monitor the fuel pressure with the pump running. The pressure should be 60-66 psi (415-455 kPa)." I monitored the pressure and it never reached 60 psi. The highest reading I monitored was 50 psi. From this reading alone I think I should be able to say my problem is either a bad/faulty Fuel Pressure Regulator or a bad/faulty Electronic Fuel Pump in the gas tank. After seeing the 50 psi. reading I then let the pressure gauge attached and checked it after setting for 1 hour, the resulting reading was then 40 psi. I then left the engine set over night for 7 hours and when checking the reading then found the reading to be 0 psi. I am not sure what the timed readings should be. I replaced my fuel filter 5 days ago thinking that was the problem, so my filter should not be causing the under pressure readings. Can 10-16 psi. cause a cold starting problem? My next question is how do I narrow the problem down further? Is there a way to check to see if my Fuel Pressure Regulator is working properly or not?

With finding that the Fuel Pressure is only 50 psi., can I safely say that I do not have a problem with my poppets?

What sensors might be schewed? I am not getting a check engine light. It has been starting kinda hard for the last 3-4 months, I just thought it had water in the tank so I have been running Heat through it I also ran a bottle of GumOut Fuel Injector Cleaner through it this week, thinking it maybe dirty injectors. However just the last 2 weeks is where it has really been acting up. When I go to start it after it has been setting for a while the engine just cranks and cranks. I found that if I turn it over briefly then shut it off, wait 5-10 sec, then turn over again and repeat this procedure 5-10 times the engine then starts, and it kinda seems that the engine is then loaded up with fuel, not sure but the engine kinda studdars for the first 2-5 secs of running.

Anyone have any thoughts on this?

Very common problem and you've nailed it. When the pressure falls below 60 they just won't fire right. Replace the pump assy. and you're in business. Kind of a tough job on the Blazer though. The fuel lines have to be unhooked right on top of the tank, takes lots of patience. Have to buy complete pump assy. I think, gets expensive.