1998 chevy blazer

I have a 1998 Chevy Blazer and it will start then it will die. I have replaced the ignition switch, and the computer,  

fuel pressure good? 

about how much pressure does it take i know on my old 1994 blazer it took 45-55 pound of pressure

i think around 60.  

i am getting ready to test it

I have a 2003 Blazer we fought a similar problem on. It always started fine. It would run occasionally without any problem, but generally would die after starting or it would idle rough one time and then fine the next. It turned out to be a bad ground strap. It was fastened well, but wasn't allowing a good ground. Ours was still under warranty when repaired and we haven't had this problem since.

I had the same problem, twice.......once I had to replace the fuel pump/filter. the next time a bottle of gas line antifreeze did the job, or seem'd to anyway......

Thae fuel pressure is 60 to 66 lbs 

How much gas is in the tank? Over 1/4 or not
 
When did you change out the fuel filter last?
 
What else does it show/do when it starts to or does die?

it has a 1/2 of gas and i change out the fuel fliter about two month ago and ran fine for about three weeks.