97 blazer ..wont start..help

ohk so i was driving it to the gym one day acted fine,came out went to start it and nothing it would turn over but not start, i replaced the fuel pump a month ago and checked the pressure today its all ok, then i noticed when i turn the key and realize that the dash is isnt working, my dad that was turning it over while iwas looking everything over said it never was working, so I then look over the obvious fuses,relays ect nothing is wrong all good , then all of a sudden boom the dash starts reading turn the key and it starts up. I drove it around for awhile drove fine , then came home let it sit went backout to start it and same thing as before , i had a computer laying around tried that , didnt do anything , so my next question would be is there any other thing that may cause this … o and i do have spark but i am kinda thinking it may be the cap and rotor whichi also replaced not to long ago…SO HELP ME

your ignition harness is bad … VERY common problem

you dont have to replace it right away … you could just jump the Pink(ign 1)wire and the White (ign. 2) wire and she will start

PM me if ya need help