2019 Suzuki 300 Surging at 1500 RPM

[tangledup]

I have twin 2019 Suzuki 300's on my boat. At around 1500 to 1550 rpms, the motors start to surge up and down by 1000 rpms. Every other rpm range they run strong and no surging. Took it out of sync and still does it. Replaced both engine interface cables and still does it. What else shall I check?

[Moonlighter]

What on earth made you think the interfaces had anything to do with the engines surging?

Are you getting any codes?

Does it do this surging every time you try to accelerate past 1500rpm?

The more info you can provide about whats happening, the circumstances, when it started, and what you have done to try to address it, what your Suzuki dealer says etc, the better, it helps people to offer suggestions.

[tangledup]

I do not have testing software. I had the engine interface cables replaced under warranty because the gauges stopped working properly. I was just mentioning this because it was the only thing that was changed, nevertheless the motors had the same issue before and after that replacement. Not sure why I mentioned that to begin with. Anyway, surging only occurs when I try to leave the motors running at 1500rpms. If I throttle up to say 1650 rpms they will hold there. If I keep the motors at 1400rpm they will hold there. 1500rpms and the motors surge up 1k and down 1k. No problem running at any other rpms at least that I saw or heard. No codes displayed on the gauges. A couple of outings it did not happen on and then it returned on Sunday.