So, we have been having engine trouble, sometimes the engine gets bogged down when towing someone and slow to respond. Not consistenlty, the engines just seems under a bigger load sometimes than others. Nothing has changed, like weight or number of people.
The boat is 2001 Supra w/5.7 330hp indmar w/ 159hrs. Never done anything except oil changes and impeller change.
So is this a maintenance issue spark plugs, timing etc? Or do I have bigger or other problems?