2018 Suzuki 300 coughing at higher RPM

[StPeteTony]

Hey folks,

Kind of what's turning out to be a project boat w/ a 2018 Suzuki 300 w/ 142 hours, has sat on a lift for about 2 seasons in Florida.

Starts fine, low rpm runs ok but won't plane, but when I ask for power to get the boat to plane it hacks up a lung.

In the video I am feeding it from a known new, good tank of ethanol free gas, it's in neutral/throttle only and hooked up to a hose. It has a new fuel filter, high pressure fuel pump and screen and high pressure fuel filter.

Take a look at the video (52 seconds), it starts coughing as I rev up (around the 39 second mark)...any ideas? Gunk in fuel injectors?

Thanks for your help/opinion...TB

https://youtu.be/oeX-3hIYYqg

[redlowrey]

Mate you wont get maximin rpm in neutral when it goes over 2500 rpm, the computer will cut injectors and spark.

[Solarman]

And Red... if it acts the same when running, it might be a miss adjusted, or bad neutral switch on the motor?


Good luck, post back on what you find out.

[StPeteTony]

I didn't realize that would be the case in neutral. Yes, under power when I ask for power it hiccups and will not deliver as i increase rpm.

[redlowrey]

DF 300 use two inputs for monitoring the neutral switch, it also uses the shift position input, if the neutral switch signal was still low when the throttle was shifted into gear, the the ecm would have seen the different shift voltage not corresponding to the neutral switch and a check engine light would have come on with a fault code.
That being said who knows how everything has been wired up but that miss is a controlled cyl miss done by the computer. If the miss you encounter is the same as in the video itis done by the computer.

Up load an other video with the engine at wide open throttle you will know straight away if it is the same type of miss.

[StPeteTony]

Do you mean a new video with the boat underway at wide open throttle?