I have a Toro 21462 that is about 1 year old with B&S engine 104M0200010F1. On occasion while mowing and the engine is warmed up, it will sputter for a split second - like it's going to shut off but then immediately resumes.  It's more annoying than a problem, but with only a year warranty left, I want to make sure if a part is defective, I replace it now.  I did find a similar issue at https://www.lawnmowerforum.com/threads/new-super-recycler-sputtering-issue.64889/page-2, and it references a possible service bulletin DSB-113/DBS-114.  Perhaps replace carb?  Un-attach and re-attach spark plug boot until it clicks?  I have replaced the plug (which re-attached the boot) but no change.  I run only ethanol free gas and it works fine in my other 4 cycle engines.  Anyone have any other ideas or had the same problem?