1991 mercury o/b was told I had a switch box go out, replaced with a cheaper set, and Still have a miss fire. It runs better, but still has a rough idle. Did I screw up buying a cheaper set?
How many other thing were changed before the box was replaced? Remember the wiring is now thirty years old. Were the plug wires replaced? Model and horsepower of motor along with history of repairs so far would be of help to try and diagnose the problem.
