What should fuel pressure be to start blazer

CPI fuel injection under intake manifold Leaking Fuel Pressure Regulator

check for gas leak if none found these had a problem with the spider injection system inside the intake cracking causing a leak and no start due to the poppet injectors not opening due to weak fuel pressure. these operate at 56lbs pressure and its critical.

Try checking the fuel filter and pump. Easy fix is the filter of course but if that doesn't work, try the pump. It is located in the tank and can be checked by seeing if there is pressure in the line going into the TBI or injectors. It is supposed to be at a certain pressure rating and there is a way to do that with a valve but that is a little more technical.

Could be the fuel pump is not providing the proper fuel pressure !
Fuel psi less than 50 psi no start GM CPI Vortec

I was given a 1994 s10 Chevy Tahoe vortex blazer??????? It's either a S-10 pick-up or it's a Tahoe or a Blazer not all three . So which is it ?

most likely fuel pressure regulator or the lines but the early style injectors cause these problems

Try replacing the fuel filter first, but it sounds like your loosing your fuel pressure prim when the fuel pump is not working. The fuel pressure should be 62-65 PSI with the engine not running the the ignition key turned on and should drop about 5 psi when the engine is running. If you turn the engine off and check the fuel pressure, it stat steady for morn then 15min. If it drops fast, then you have a leak at your fuel pressure regulator (common) or your return fuel check valve which is located at your fuel sending unit.
Start with the simple and replace the fuel filter, it could just be to dirty to pressurize the fuel system fast enough giving you the hard start.
Thank you for using Fixya and good luck

you either have a clogged filter or a bad fuel pump.

probably not fuel filter . probably going to have to remove the upper intake and replace the fuel injector spider(fuel inj assebly) if it is droping fuel pressure it is leaking into the upper manifold

the problem is common for the 93-94-95 4.3 vortex its the spider injection located inside the plenum the part costs between $250 to 400 i had to replace on girlfreinds 94 blazer. ifound one o ebay for $100