Carb cleaner works real good on Evinrude
E-Tec injectors, too. Had the SA agent tell me that the "injector was shot" on one of my inshore survey
boat motors and as the motors were out of warranty, he wanted to fit a new one. The cost of a replacement is astronomical and the agents show no mercy, so I went all practical as yotties do and happened to find an old can of Quicksilver Carb Cleaner left over from servicing my 10hp Mariner years ago. Worked a treat and dissolved the little speck of muck. Injector has not misbehaved since ( just remember to fit the injectors in the same location - ie : don't mix them up). Carb Cleaner should always be in the spares box.