Did it cause it to run on 4 cylinders in forward ? I guess there’s an exact spot it has to be in.. Hopefully when he hooks it back up he can dial it in.

when its idling out of gear it just runs on 4 when in gear it picks up the other 2 on a hpdi

Mine did this and it was a very dirty O2 sensor. I clean it all the time now. Like many above have stated that fuel system can be tricky. The VST needs to fill properly its very easy to get something out of wack in there.

only vz motors that have 02 sensors are the older 2.6 liter engines not the hpdi series two 3.3

Here’s the numbers from side plate would it have an O2 sensor
YAMAHA. VZ225HTLR
60Y L 11006566
But it’s a 3.3 so I guess not

If my mechanic can’t figure it , who would be the best Yamaha guy between Dallas and Tyler?

I use Service Marine in Emory.

If my Yamaha is trimmed down, good luck getting it to start.
If I trim it up, it starts right up.

Well he might have figured it out. Long story short, Coils got mixed up during the rebuild, supposedly two of the six coils are different from the other four. So gonna try and find the the two that go on 5 & 6 cylinders and hopefully get'er goin again. I looked up the part #s and the bottom 2 have a different number. Crossing my fingers.

At a different mechanic now, still scratching thier heads

Same here. That’s a good group of guys. Honest and fair in my experiences.

I just went through the process of chasing a gremlin on a Ox66. Not exactly the same, but in my case it was a ground issue. When things get weird, t could be sensors, something that changes when motor moves, or maybe grounds. Go back to the basics. The motor needs fuel, spark, and air to run. Which one is failing?

Just not much power in forward, takes forever to plane out. It jumps off trailer backwards but forward it’s like on 4 cylinders. Idles fine.

Which shop did you take it to?

Sounds like it may be the switch in the control box that kicks it to all 6 cylinders