Two days ago my 2000 model C-115 would not plane off the boat as normal and it would bog down when advancing the throttle. At idle I pulled each plug wire individually and found that one plug wasn't firing. The engine idled as fine with this particular plug wire off as on. I changed the fuel filter and checked for water- none. I installed four new spark plugs. Still I had the same exact problem. I ran the boat a while and suddenly the problem disappeared and the motor ran fine. I ran the boat yesterday and the motor ran great. Today the same problem occurred and again after running the engine a while the problem disappeared and the motor ran great again. Any suggestions as to how the fix this problem will be appreciated. Thanks.
