I have made progress on this car since I first bought it but still has a miss. I am pretty sure it is out of the number 5 cylinder. This is because when I put my fingers on, when running, the injector it is ticking more than the others. The plug is dark but no carbon build-up. I switched plug wire 5 with another (and on the cap too) to make sure it wasn't the wire... same thing. This can has splitfire plugs and are all gapped the same. I did not switch the plug itself since it looked good and gap was right. It is pretty new and seems fine.
Am I skipping a step? Should I discard all the splitfire plugs for OEM? I have heard people having issues with splitfires in the past.
Is the "tick" being more than the others a sign the injector is bad? If it was not getting gas though, would'nt the plug be close to white on the tip from sparking without fuel? Should I just take it to a shop and let them charge me a small fortune because they have diagnostics? No Services Engine light is on but the car just doesn't want to quit shuttering when in gear. Lack of power but driveable. The CAT will need to be replace soon as it rattles but I think some of this is due to it not running smooth. I did adjust timing both retard and advance but miss is still there.
Any helpful suggestions?
Thank you in advance.

 

Timing won't affect a single cylinder.

No love here for expensive spark plug gadgetry. But, wouldn't hurt to switch the plug with one from a cylinder that isn't misfiring.

Have you done a compression test?

Are you sure you have the spark plug wires going to the correct cylinders?