2003 225 vmax skipping

[ronnie]

I have a 2003 yamaha 225 vmax that skips on 2 cylinder right off idle under load. No fire getting to those 2 coils. The triggers under the flywheel test good on all 6. The tech thinks it may be a bad ecu which cost about 1200.00 but is not completely sure. Any one else seen this.

[boats.net]

Some of the OX66 models only idle on 4 cylinders and start running on all 6 at about 1200 rpm's.

[ronnie]

Thanks for the info. I was told on some models 2 and 5 cylinders cut out rt off idle for *****ing. Mine is cutting out 2 and 4 cylinders. And will bogg real bad on hard accel at times. Could 02 sensor cause this and should this engine cut 2 cylinder out or not. vx225tlrb 2003

[jb123]

sensor info :

http://www.boatsetup.com/O2sensor.pdf

my personal exp with bad sensors is varying hi rpms and no max.
( I ) would pull each plug wire while running, above 1200 on the hose and listen for definate fire, even if you have to pull 2 to hear it.

could it be a non firing injector?
is the plug dry ?
have you ever cleaned the vst filter??

[jb123]

and you HAVE swapped the coils and wires, yes ??