2001 Yamaha HPDI 200 Cuts out intermittantly... factory gauges too.

Not a mechanic, but know how to use a wrench.

2001 Yamaha HPDI 200 has started a new habit of intermittantly cutting out at all RPMs. Yamaha gauges go blank occasionaly during engine cut-outs and try to dimly come back. In time, all comes back and operates normally. During last failure I ended up in the engine fuse panel and noticed when the O2 Sensor fuse was PULLED gauges lit up as normal, when fuse was RE-INSTALLED gauges went blank. Consistently.

Have:
-Added "ring free" anytime ethanol fuel has been added.
-Cleaned and tightened ground connections at motor and batteries.
-Inspected for loose wiring connections where possible.
-Recently replaced fuel water seperator, sparkplugs, impellar, 9.9 kicker motor.

Any suggestions, thoughts, or ideas are greatly appreciated. Thanks.

Re: 2001 Yamaha HPDI 200 Cuts out intermittantly... factory gauges too.

Gauges that die at the same time the engine does points to electrical. For both of those to happen there would be an intermittent connection either at the battery or somewhere between it and the ignition switch, back to the engine. You checked the ground connections but did you check the positive cable as well. And did you check both ends of the cables. Doesn't do any good to clean one end and not the other if that's where the problem is.