OK guys don't shoot me for this, but my '01 ski boat with a 320HP Chevy 5.7 Indmar TBI (just like our trucks) is giving me fits. I have posted on boat forums but those guys only talk about polishing thier teak ski platforms and crap like that. At the end of last summer, it began running very rich (black, sooty smoke) and started fouling plugs badly. It would run OK (minus the smoke and the bad gas milage) for 1/2 of the day. Then the plugs would get all fouled up and it would become hard or impossible to start. Someone recommended replacing the temp. sensor. I did this and it did not help. I got pissed at the end of the year and put it up with the intent getting it to the dealer over the winter. Well, you guys know the story, summer is here and my boat is still sitting there untouched. Any advise on this? I hate to take it in now, it will be winter again before those idots at the dealership get it fixed (not the mention that boat dealers rip you off 5 times more than the car shops)! If it helps, I have the complete TBI system off my '87 K5 with almost all new sensors (MAP, TPS, etc.). Where should I start?