Hello, I am new to trying "online help" but I tried everything I know with no results. The motor idles nice and smooth in and out of gear but when I start to go it runs perfect for about 20 seconds and then starts running really rough, I have learned that I can either turn the key off and on real quick and it runs fine again for about 20 seconds, or bring it back to an idle and go again it will run really smooth for about 20 seconds then start its rough idle again. I have put a spark plug tester to each of the three plugs, at an idle all appear to fire fine, however when rev-ing cylinder #1 continues to fire as it should, cylinder #2 and #3, loses spark after rev-ing for about 20 seconds. again I can turn the key off and on real fast and all cylinders fire as they should for about 20 seconds. I can also bring it back to an idle and rev back up it will work as it should for about 20 seconds. I have tested the oil level, oil pressure sensor, temp sensor, engine temp, timing, timing belt, replaced impeller, inspected for clogs in the water routing. changed spark plugs, changed engine oil, lower unit oil..... there are no warning lights on or buzzer sounding the green light comes on as it should. I have been messing with this and have had no luck for about 6 months, any help would be very much appreciated.