DarrenShumbo
New member
I have a 1994 Evinrude 175 two stroke with an idle speed misfire. Good compression, carbs are perfect and just rebuilt, spark plugs are new. Wires seem good. Spark in all cylinders seems good as I checked them with a tester. It seems one cylinder is misfiring every 2 or 3 seconds..It runs smooth, then misfires, then runs smooth again. I have seen this on two engines this year. They do the exact same thing. One engine has brand new coils , wires and plugs and perfect carbs yet does the same thing. The mixtures for the idle seems good and has been adjusted to both over lean and also over rich but the problem persists. Anyone on here have an issue with the cdi box that would cause this only at idle ? I do not want to just buy a cdi if it is something else someone else may have come across. I am a marine and aircraft mechanic for over 50 years. This problem seems to pop up every now and then. Any ideas ? Thanks ! 
