Not sure about the limp mode, someone else may know more. I’ve learned that pumping the oil and transmission fluid out rather than draining is better (for me anyway) so I can put the exact amount I pumped out back in. An example is I just changed the transmission fluid and filter on my hurth. Everything I read said 2.13 quarts but it actually took almost 3 whole quarts which is what I pumped out.Now that I'm thinking about it more, it may not be the transmission after all.
Basically what happened is I'd advance past 2000 rpms and it would cut the power, the revs didnt rise but fall. I would think if the trans slipped the rpms would rise instead of drop.
So I suppose I may have some sort of electrical sensor issue with this TBI system. Would this engine maybe have a limp mode that it's activating? Not sure where to start with these sensors.
Thank you very much! Appreciate the advice.I've not been paying attention to this thread for a while. I agree with others here that you've done an amazing job with this boat. She's beautiful, and you should be very proud!
I'm not fixated on the tranny in your case. I've had one slip, and I've had one internally destruct. You are correct that the revs spike during those events.
Now to throw some things out regarding the rpm dive. Fuel pressure and volume are the most common causes of low rpm. If your fuel pressure or fuel flow is good at idle, either or both may drop off at WOT. I remember you have the new fuel pump (because I bought one too!), but I would check the fuel return lines, fuel tank valves,, and most importantly, the fuel tank vents.
But before you go taking stuff apart, get a 5 gallon (or so) gas can and take her out for a spin running off the gas can. If she revs fine, you will know that the issue is in the fuel lines, filters or tank vents.
Lastly and maybe... did you mess with or adjust the engine timing (should be 10°BTDC)? Is it jumping around at idle? If so, the computer was not put in diagnostic mode first in order to set the base timing. Does she rev up and hold revs fine in neutral?