The absolute first thing to check with ANY electronic ignition is, are you getting spark at a plug? Disconnect any plug wire (#8 is convenient), attach the plug wire to a spare spark plug and attach a ground wire to the steel plug's shell. Crank the engine: if no spark, change the module. O'Reilleys Auto Parts (formerly Kragens) has them for $37-$40.
Like 100% of electronic ignitions, the module will fail whenever it feels like it! I carry a spare along with an extra e-coil, which by the way is a valuable upgrade to the std Duraspark ignition, 'cause e-coils do not burn out. Can-of-oil coils do and usually take the module with them.
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