car has a pretty decent stumble to it, my #4 plug wasn't getting spark., put on a brand new ac delco opti, same problem, all my plug wires have continuity, what could my problem be? been dicking w/ this for 3 weeks now, any help is greatly appreciated.
-Jason

 

I assume you scanned the car since the said #4. After the opti still the same plug? Change the plug itself? I have a 95 with no misfire code but I thnk if you know what cylinder is missing you could narrow it down fairly easily. Good luck with it man