this one is a tough one
 

I have a 1996 s10 blazer lt, i blew a fuel line about a week ago. Replaced the fuel line wouldnt start, so i checked the spark, had spark but didn't seam good enought so went n baught a new rotor n cap sparks great now. still wont start.. so went out n baught a fuel pressure checker to check the fuel pressure at the rail.. first prime it will be about 60 psi, about 1min later falls off to about 55 psi. when i go to turn it over it falls to 40 psi on crank could this be the problem and causing my blazer not to start. the truck ran great b4 i blew the fuel line. could the fuel pump be no good now from sitting with no fuel in it for 4 or 5 days. hopefully some one knows the answer im at wits end with this truck its been a week now n still havent gotten any where

Have you tried starting fluid to get it going and see if it runs at all?

yeah it will kinda start on starting fluid run really rough then stall when the fluid burns off

Sounds to me like you still have a leak somewhere in your system. Do a proper pressure check and see what kind of results you get.

a proper pressure check as in how? i connect the fuel pressure tester up off the schrader valve(i know i spelled it wrong) and i turn the key to on to "prime" the pump and i get 59-60psi.

Yeah then you turn the key off and let it sit and see what your pressure is at after 10 minutes. If its any lower than 55 give or take then you still have a leak somewhere.

I guess technically that's a leak down test rather than a pressure test!

and if it passes the leak down test then im back to the beginning of not know what is wrong with it. i just dont make too much sence it ran great b4 the line blew, and it would start every hour or so for a few hours after i got it home then the next morning it wouldnt start

Well then don't try the first logical place to start diagnosing what seems to be a fuel issue that's cool! It may not be the issue but its the easiest place to start to narrow things down.

oh im going to do a leak down test, basicly the way i was putting it is if that isnt it then where do i go from there

you said in your original post that it drops to 55 after about 1 min. it shouldnt drop below that after TEN mins. i would have also suggested a leak down test just like Rex has. it just seems like its falling too fast to not have a leak. do the leak down and post your results and then we can go from there.