Hey guys I have a 25hp two cycle, tiller handle Johnson motor 97' model. Motor always starts and runs great with one exception. I like to fish below dams and what we do is pull up to the generating dam and cut to idle and drift back for 800-1000 feet and then throttle back up and do it again. When I throttle back up to head to the dam the engine sputters and coughs. I will go back to idle and try again with same results. Usually after about three tries, she gets full power and I run back up to the dam no problem. This only happens after I have been running and then idling for a few minutes or more. Any ideas?? Carb ice?? Garbage in the line??

Any help appreciated
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