Will crank but not start changed cap and roter changed plugs and wirs

Could be no fuel.

How are you testing the thought that there is no spark to the plugs? If you had no spark to the plugs, you'd also have no backfiring. Backfiring is evidence of a fuel - air ratio concern, or some kind of emissions control or exhaust system issue where air is getting where it isn't supposed to be. Hands on testing is needed. As Scott said - could be no fuel -- what testing has been performed?