spark, electrical, or fuel problem! need help

I PURCHACED a 97 tahoe that i knew needed some fixing but now after replacing what i thought the problem was i'm stumped! it has a stalling problem... it will start but kill quickly... if i start it and put it in to gear it will last another 30 seconds but than kill shortly after that... i ran a scan and found i needed a new crank sensor so i replaced that and it still has the same problem... i also replaced the ignition module and that seemed to fix the problem but after a 15 minute drive it started to do the same start stall thing all over again..... i know i have spark but it is a little weak and i am going to replace the plugs and wires within a few days here but i don't believe that is the sole problem! the fuel pump was replaced 7 monthes ago and is in \working condition. any input is highly appriciated!!!!! just need some new ideas! (also,i should add, on that drive after relacing the ignition mod it didn't kill at first but skipped. the rpms went all the way down to o but than shot right back up as if nothing happened.) i hope thats enough info! thanks!!!!

Welcome to AF. For diagnostic purposes, I'd check the fuel pressure.

Will Do So Tonight! Thanks....

Will Do So Tonight! Thanks.... ACTUALLY TOMORROW, TONIGHT I'm busy...

This May Sound Like A Stupid Question To Some But Could Bad Or Defective Spark Plugs Or Wires Cause A Large Enough Strain On The Distributor And Ignition Mod To Cause Them To Go Bad? Or Is This Whole Scenario Just A Bad Theory?

It is possible the wires could get tired from having to carry max voltage to fire bad plugs, but that is a stretch.