1999 blazer no spark

I have a 99 blazer with 4.3 vortec that iv been working on. It ran rough since then weve replaced fuel pump,filter, distributor cap, rotor button, plugs and wires. Also coil,distributor,crank sensor 5v,map sensor and still no spark but fuel pressure is 60psi. We put fuel pump on and filter ran ok for 2 days then shut off and had no spark so replaced crank sensor and ran good for few days and same thing again no spark so replaced coil and ran good for few days and same thing no spark. So yesterday i put new disributor and map sensor and it started and ran perfect. Took it home and this morning i started it and drove to end of driveway and it died and again no spark. Im at a loss and dont know what else to check or replace.. Please help

I have a 99 blazer with 4.3 vortec that iv been working on. It ran rough since then weve replaced fuel pump,filter, distributor cap, rotor button, plugs and wires. Also coil,distributor,crank sensor 5v,map sensor and still no spark but fuel pressure is 60psi. We put fuel pump on and filter ran ok for 2 days then shut off and had no spark so replaced crank sensor and ran good for few days and same thing again no spark so replaced coil and ran good for few days and same thing no spark. So yesterday i put new disributor and map sensor and it started and ran perfect. Took it home and this morning i started it and drove to end of driveway and it died and again no spark. Im at a loss and dont know what else to check or replace.. Please help

Any codes?
When no start is the pcm/vcm getting a rpm sigal?

i didnt see you replaced the control module?

i actually figured out the problem. the parts store gave me iridium plugs so i put regular ac delco and it is now running 100%

thanks alot though for the help

i actually figured out the problem. the parts store gave me iridium plugs so i put regular ac delco and it is now running 100%
That would not cause a no start.
You have other problems.:uhoh:
It should have platinum 41-942 used in it.