Replacement of spark plugs

[Lpolk]

I replaced all 6 spark plugs and no change. The low level miss continues. My question is will it hurt the motor to operate it, a few more times because, The local shops are so busy until I probably wouldn't get my boat back for weeks. Not being a machanec with very few skills, what should I look into next.

[EuropeanAM]

Larry:

Before we get too much deeper into the discussion of your low-speed miss complaint, can you identify "which" 2006 ProXS you have (specifically)? Preferably include the engine serial number....

[Lpolk]

I do Apologize, we are talking about a 225 Pro XS with 73 hrs, year is a 2006. Serial# IB-379905. A first for the spark plugs. This just started, it's not a complete cut out , just a noticeable miss when in idle. Motor haven't had anything done to it except the plugs and minor maintenance, nothing major.

[EuropeanAM]

Thanks, Larry! That certainly helps!

Slight off-idle or at idle misses are usually caused by plugs misfiring (you've already replaced- look carefully at plug wires and routing also), dirty direct injectors (carbon fouled), poor-quality fuel (mid-grade or 89 octane has been known to improve this- especially in warmer weather), and several other items (such as a TPS that's malfunctioning, or a sticking-open thermostat).

I'd suggest looking at your engine temps, and perhaps a tank of mid-grade (89 octane) fuel as the first steps in trying to address this. Make sure you're running AT LEAST "Quickleen" in EVERY tank of fuel.