Misfire on 2008 SV 211? Causes?

[ksuich01]

Question for the group... I have a 2008 SV 211 with 343 Engine and GPS Speed Control. Boat runs great, but I have noticed if I am traveling above 25 MPH and then ease off the Throttle to ~ 23 MPH the engine seems to Misfire and run a little "rough"? As soon as I either decrease or increase the speed the misfire goes away.

Speed Control is Off, and issue has not seem to get worse, I just wander if it is something simple.

Any ideas what may be causing the misfire?

[nukemustang]

Have you ever replaced the cap and rotor? I know on my 07, I just replaced it and it was full of corrosion, but this could cause cross-firing or miss firing. start simple.

Tim

[theskunk]

When was the last time your knock sensor was replaced?

[ksuich01]

Thanks Everyone... I was thinking Cap/Rotor (maybe plugs and Fuel Filter) but didn't think about Knock Sensor? Do you have any more details on the Knock Sensor

[theskunk]

http://www.planetnautique.com/vb5/fo...-knock-sensors

Sounds like you actually have two of them.

One of these should be it. Don't forget you get 10% off at NP.com with the coupon code in nautiquejeff's signature.