Ok, I'm the third owner of a 2005 4200 Ventrac. It was not running right back in June, kept cutting out and not restarting, so I cleaned the wires that connect to the ignition module, that seemed to help quite a bit. Now its missing and cutting out again. Whata ya think?
I would also check for engine to ground and any other ground wires for corrosion , You state having checked the wiring to the ign. module. Did you check for water or contaminate in the fuel system? Do you leave fuel in the tank over winter or did you shut off the fuel and run it dry to remove fuel from the carb bowl at the end of the season. Old fuel can foul the small porting in the fuel system creating the issues you describe.
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Let us know if this helps, thanks, Marks