1997 GMC C1500 no spark

I have a 1997 gmc 4x4 1/2 ton with a 5.7 vortech that im not getting a spark. ive replaced the cap rotor and pick up coil in. ive test to see if i have power to the coil an crank sensor. i do so and power all the way up to the cap and rotor. ive had the module tested and it test ok. ive check all the fuses and there also good. so question is what else could be my problem??? ive gone threw about every thing i can think of and what my book on the truck said to but when i crank the engine there is nothing at the plugs. i do have a spark at the coil but dont seem like it the best but will light up a plug. so if there any thing that i havent check or done please let me know and thanks for looking into this for me...