Yamaha 115 Behaving Badly

[Katie222]

Hello All,
I'm hoping to tap into the wealth of knowledge here before we haul our misbehaving outboard into the shop. Our lodge has twin Yamaha F115 outboards and one has started to run roughly about 50 hours ago.

Engine Specs: - 2009 Yamaha F115 TXR, 4 Stroke
- 1200 Hours, regularly maintained

Symptoms: - Runs rough, RPMs jump 2-3K, lots of engine shaking
- Only runs rough at certain RPMs (~15K, 25K)
- Runs fine at idle & higher RPMs

Troubleshooting: - Primary Fuel Filter/Water Separator Replaced
- Secondary (In-Line) Fuel Filter Replaced
- Swapped Ignition Coils with other engine
- Checked Spark Plugs & Gap

It is time to take it to the shop to take a look at the injectors and VST Filter? Any thoughts on other items to troubleshoot before that step? All ideas would be appreciated!

Thanks,
Katie

[Mayport Diver]

If you haven't had the VST filter cleaned then I would start there then injectors. I had a similar issue and it was both with my twins. I pulled the VST, cleaned filter then took the injectors to shop. Reinstalled and they have ran well ever since.