Mercury 150 hp 4 stroke EFI - WOT issues

[putt putt boom]

Hey Guys,
I have a 2013 mercury 150 4 stroke EFI outboard on my Tritoon. It runs as it should till I get about 3/4 throttle. Anything over this the engine will forcefully shake really bad and bog down. I bring throttle down to neutral and can immediately reengage throttle. I don’t know much of anything about engines so I appreciate all your input.

 

[putt putt boom]

I had a mobile boat mechanic come out and unfortunately the engine is not throwing any error codes. I did swap out the spark plugs but that did not work. I also had a 300 hr tune up at 100 hrs just in October. I do not feel it is fuel related.

 

[Texasmark]

Don't guess, get a small can of fresh fuel and see what happens. WW has tanks and you can keep it for an emergency spare.

Having 300 hrs on the engine, when is the last time you changed the fuel filter in the engine proper, ofrxternal also if you have a water separator hootus.

 

[Faztbullet]

Need to have it scanned when it is acting up...could be a MAP or TPS going out of range or a IAC acting up.

 

[putt putt boom]

The boat only has 116 hrs on it. I was just referencing the service I went ahead and had done (300hrs) fuel filter was replaced October 2019. The mechanic that came already ran the fuel tests and cleared the fuel. As far as running tests while it happens is that it only happens for about 10 seconds. Not long enough for his scanner to pick up anything on the diagnostic check. I will try to post a video but struggle to save it from my phone as a different source. It won’t let me upload a .MOV file from iPhone.
thanks guys!

 

[putt putt boom]

https://youtu.be/7HWmf4gHOCg

here is a video from my Tritoon. You may need to copy and paste it into your browser.

 

[Faztbullet]

Does the engine alarm horn work and does it beep when this happens? Also check the shift switch as may be out of adjustment...

 

[putt putt boom]

No alarms or codes. Had the tech come out again. We are using Marinemax as the vendor. Here are the notes from work order:

Job #DIAG - External
COMPLAINT: DIAGNOSIS OF CONCERN USING STANDARD PRACTICES AND EQPT. VERIFY CONCERN AND ESTIMATE REPAIRS
CHECK SPARK, CHECK COILS, CHECK PLUGS,
MOTOR SEEMS TO BE LOOSE POWER MID RANGE FOR FEW SEC SPERTS.
CAUSE: REMOVE CAWLS, VISUAL INSPECTION OF HARNESS. CHECK FUEL psi, OHM COILS, OHM INSPECT TERMINAL AT COILS, INSPECT FUEL RAIL, TAKE FUEL SAMPLE, REMOVE RAIL AND INSPECT INJECTOR SCREEN. OHM COIL/PLUG WIRE. LAKE TEST. NO CODES, FAULTS.
CORRECTION: INTERMITTENT MISS/ROUGH RUNNING HAS NOT BEEN DUPLICATED. RECOMEND REPLACE SPARK PLUGS, INSPECT COILS. NO VISUAL PROBLEM FOUND. COIL, WIRES OHM TEST IN SPEC. LAKE TEST WITH NO ISSUE. 1. REPLACED SPARK PLUGS. 2. REMOVED INDUCTION HR METER. (WILL FOLLOW UP AND SEE IF PROBLEM PERSISTS)
COMPLAINT: REMOVED INDCTION HR METER WRAPPED AROUND COIL SECONDARY WIRE. COIL

we have so far spent about $800 and all we get is we can’t duplicate the issue.