MisFire on F225TURA

[sreskunked]

I have had a small misfire under acceleration although you could accelerate right through it. The other day I went out and could not get the boat on plane or the engine to rev above 3000 rpms. I took the boat back to the dock and got several bottles of injector cleaner. Poured it in and went back out. Was able to slowly accelerate and eventually get it to run clean. After fishing and driving around the rest of the day with no problem, I pulled all plugs and found #1 cylinder plug to blacker in color than all other. The porcelain on all plugs where brown although #1 had black soot on it. I also have changed the water separator and found no sign of water in the fuel. Took the boat out again and has a small misfire at idle in gear and misses a couple of times when dumping to full throttle from idle. Is it possible that I have a bad coil or what do you guys suspect. The motor is a 2002 with 140 hours.

 

[bigbrownbuku]

Re: MisFire on F225TURA

how old are the spark plugs? has there been any work on the throttle bodies? a 2k2 engine would have had the throttle link rods changed and may have needed resyncing.

 

[sreskunked]

Re: MisFire on F225TURA

No there has been know work on the throttle bodies. I changed the plug on the #1 cylinder which is where I think the problem is. I am thinking of swaping the coils around and see if the problem follows to the new location of the coil.

 

[rodbolt]

Re: MisFire on F225TURA

the coils control 2 cyls each. its a TCI ign system. its ok.most likly a ISC going bad or a VST filter clogging. it could be an injector filter cogging but usually that will show up at high speeds.<br /> but run the primary ID numbers to a yamaha dealer and see if all the updates that are applicable have been done. could be as many as 3<br />that need doing.

 

[sreskunked]

Re: MisFire on F225TURA

 

[sreskunked]

Re: MisFire on F225TURA

Thank you for your help. Should I just call a local dealer and with the numbers they can tell me if I need updates on this engine.

 

[rodbolt]

Re: MisFire on F225TURA

yes. exactly