Ok, I'm still having problems with my 94 Jimmy 4.3 CPI.

Problem - Wont Start on its own. Must use Starting Fluid. Fuel Pressure is 45-50 psi when trying to start and is a constant 50 psi while Idling. Once running it runs like a champ, no stalling or bucking, nothing. Can drive on the highway at 70 mph, without worries.

Things I Have Tried -
Fuel Pump Relay replaced, no help
Used Spider Injector swapped in, no help
A New Fuel Pressure Regulator installed, no help
New Fuel Filter put in, no help

Suggestions - ?????

I havent done the fuel pump, becuase I believe if it was the pump it wouldn't run at all or run like crap. Please help, I'm tried of having to pop the hood and spray fluid into the throttle body everytime I want to go somewhere.

 

It could be the pump
your pressure with the key on should be around 55-60 from what ive read/heard

 

do yourself a favor and use carb spray instead of starting fluid.

.. try turning the key on and off a few times before starting it.
let it sit on a few seconds each time you turn it to run...
check the schrader valve on your fuel rail make sure its good and snug.

mind you i have little experience with these 4.3 blazers this is just general diagnostics on FI starting issues

 

I have tried letting it sit and build pressure for a few sec's.

Why should I use carb cleaner over starting fluid? What am I doing wrong?

 

Agree it could be the pump. Your pressure is a little low. Any codes?

 

The SES light isnt on and it hasnt come on. Could there be codes stored in there?

Why Carb cleaner over Starting fluid?

 

carb spray is less volatile and alot easier on your combustion chambers sealing areas. less hard on the motor in general

 

I checked the OBD and I dont have any codes stored, the Light wasnt on, but I figure I would check anyway. It just kept flashing 12. Probably going to get a new pump this weekend and replace that and see what happens.

I should go to NAPA and get a AC Delco replacement part right, not a Autozone or Pep Boys brand?

 

Get the Delco for sure. it wont be that much more. Ive gotta get myself a pump too on the way home from work tomorrow. Lets compare what we get them for. I got to a canadian NAPA store to get all my stuff.

 

alright I'll let you know. Are you going to do the exchange rate, I'm not good at math.