HPTI stalling on acceleration

[skeeter74mph]

have 175 hpdi idles great!!! top end great! when hitting throttle to get up on plane it cuts out like off on off on.Then takes off and runs great. cleaned gas tank and changed all filters..... no water present all lines hold pressure. does not lose prime. was thinking electrical but I am clueless with these newer motors. It will do this everytime i go to take off hot or cold

[99yam40]

so, are you sure the rail pressure holds steady while this problem is happening?
if it does, then you are left with injectors not firing on all cylinders or spark/timing problem.

those motors limit RPM while in neutral by dropping some more cylinders,
so maybe a switch that tells the ecu it is in gear is getting flaky.
just a wild guess

[DennisG01]

Is this a new or on-going problem?

Are you sure you're not confusing a problem with the cylinder cutout feature? In the 2,000-ish RPM range, it doesn't run on all cylinders so if you throttle up too slowly it will do exactly as you describe.

EDIT: I should say that "I think" you have cylinder deactivation in the 2,000-ish range. Mine does and I "thought" your engine was similar in that respect. Check into it.

[skeeter74mph]

We’ve had this boat for four years and never had a problem like this. Just started this year. If it was a cylinder deactivation, would it only happen on a slow throttle increase or on a floor throttle increase. Is that since there something I can change on my own?

[DennisG01]

We’ve had this boat for four years and never had a problem like this. Just started this year. If it was a cylinder deactivation, would it only happen on a slow throttle increase or on a floor throttle increase. Is that since there something I can change on my own?

If it's cylinder deactivation (Google or your service manual would likely clarify that) you would NOT notice it with at least "medium" acceleration - only with slow acceleration.

If this is not the case, then hook up a fuel pressure gauge - monitor that while accelerating. They are not expensive to buy.