I can't comment on how your timing light is permforming--maybe the inductive connection isn't sensitive enough to pick up all the signals--or the spark plug wire or condensor is not 100%--or points bouce--but I did want to mention, regarding the advance -- if the spring back is not positive, the internal groove in the shaft sections is probably gummed up -- that's what gets lubricated when you add a drop of oil under the felt pad in the shaft center -- and the weights may be worn at the pivot point causing sloppy looseness--and/or the springs stretched. I can mail you, on loan, any number of distributors while you investigate your own.