Yes. It could cause the timing to be, well, to be too advanced. Hahahaha
I think that this would show up under heavy load, flat out in fourth from 20 mph.
Running hot can be the timing too far advanced.
Have you verified the timing statically? Multi meter across the points, just breaking contact at the mark?
Running lean can cause this too. What about a vacuum leak?
Does this happen right off of idle?
