1992 jimmy won't start one day, the next day it does

hi guys i'm new to your forum, and i've read 3 or 4 posts concerning my problem, the concensus seems to be that its my fuel pump gone bad. i have a 1992 gmc jimmy slt 4.3 vortec 4x4. my truck has just become more and more unreliable,of course when it does start i've had a mechanic tell me there are no error codes, but i have had one mechanic tell me the electrical signal from the pump is really low so that could be the problem, my cap, rotor and wires are good, i've also read on some posts to check the fuel pressure but i'm not sure on how to do that. has anyone else had the same problem with their 1992 jimmy ? my truck turns over but won't start one day, the next day it'll start, sometimes i can leave it 10 minures then it'll start, so its pretty strange and frustrating when it does start and ofcourse it'll start in front of a mechanic with all his gear out ready to test it LOL, i'm just about at my wits end, just about ready to sell the thing. just curious if anyone else has had the same problem thanks for your advice, i really appreciate it :)

Do you have the orange vortec plate on top of your engine?

If so, do a search for CPI injector here and in the Blazer forum for more informaiton.

thanks for your help blazer lt but i have replaced the cpi injector about 3 years ago, could it be time for it to be replaced again?

Have you done a tuneup lately?

Checked fuel pressure?