I have a 1999 blazer with the 4.3 engine and the dang thing will start somedays other times it wont I just put in a fuel pump a few weeks back and it was fine for like 10 days then it started dieing and will not start back up. its like the 4th time it has left us stranded. If u squirt starter fluid in it will start , o I think its something will pump. Any of u guys have any ideas oh ya some times it will start up and run for like 5 minutes then die and wont restart. thx in advance for the help.

 

fuel filter?

 

I think rich is right. I ran into this very recently, mine was a pump and a filter tho. Gotta love cheap buys!

 

What brand of pump did you use?
Search around in here. There have been a LOT of similar posts about start won't start, falls on it's face under acceleration, dies at lights etc.

 

If you didn't use a Delphi or AC Delco pump that is most likely your problem. But to be sure hook up a pressure tester & post the pressure when you turn on the key should be 60 psi. Then turn off the key & see what the pressure is after 5 minutes. It shouldn't drop more than 10 psi.
You should always install a new fuel filter with a new pump.