Hey guys, this is my first post here but I've been an avid reader searching and finding solutions to my car problems. My 305 finally pooped out on me a few months back so I decided to go ahead and swap in a 350 Vortec. I retained my ignition system and bolted up a carbed Vortec intake with the tbi adapter and I've got everything hooked up but my only problem is I don't have any coil spark. I've downloaded, printed, and gone through the "No Spark" troubleshooting tree but I keep getting to the end and being told i need to replace the coil but i've already done that twice (second time just to make sure the first one i bought wasn't defective out of the box). I wanted to refurbish my ignition system anyway so I've replace coil, wires, plugs, distributor, cap, rotor, icm, and pickup but no dice. I'm completely puzzle, does anyone have any advice? or better yet does anyone know what i can check that will prevent my coil from sending out the spark to the distributor?

BTW i've searched the threads here and other forums but no one is quit having the issue I'm having because i do get injector pulse every time i try to crank.

 

If your 100% certain you have a good source of +12 Volt power on the fat pink wire going to the ignition coil , and that you have the wires connected correctly between the pickup and ICM , and ICM to ignition coil , and have proper continuity of the pickup coil , and have tried two different ignition coils , my biggest suspicion would be that the new ICM you bought is defective and to try a different one , maybe even from a different dealer .

That is , of course , providing you have actually visually verified that the distributor is in fact spinning while cranking the engine over with the starter ?

And that you don't have something grounding out the white "tach" wire from the coil ?

PS , Welcome to Third Gen . org !

 

thanks for welcoming me and thanks for the help. In response to what you've stated:

1. I am getting +12v to pink wire going to coil
2. pickup is connected to ICM and resistance was checked and in acceptable range
3. icm was replaced twice. after searching here i thought i concluded the icm was bad so I replaced it. That didn't do the trick so I started looking a little closer and realized my reluctor atop the pickup had multiple cracks so I replaced the whole distributor with all the accessories.
4. i heard the engine run before i bought it and verified distributor turned before engine was swapped and afterwards.

finally (sorry for the long post) im not 100% sure which wire is the "tach" wire. from my research I'm assuming its the white wire next to the pink one on the gray coil connector? if so, i've back tracked that wire too!